Research ArticleOne-Step Synthesis of Copper and Cupric OxideParticles from the Liquid Phase by X-Ray Radiolysis UsingSynchrotron Radiation

Akinobu Yamaguchi1 Ikuo Okada2 Takao Fukuoka1 Mari Ishihara3

Ikuya Sakurai2 and Yuichi Utsumi1

1Laboratory of Advance Science and Technology for Industry University of Hyogo 3-1-2 Koto Kamigori AkoHyogo 678-1205 Japan2Synchrotron Radiation Research Center Nagoya University Furo-cho Chikusa-ku Nagoya Aichi 464-8603 Japan3Hyogo Prefectural Institute of Technology 3-1-12 Yukihira Suma Kobe 654-0037 Japan

Correspondence should be addressed to Akinobu Yamaguchi yamagutilastiu-hyogoacjp

Received 28 September 2016 Accepted 22 November 2016

Academic Editor Fuxiang Zhang

Copyright copy 2016 Akinobu Yamaguchi et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The deposition of copper (Cu) and cupric oxide (Cu4O3 Cu2O and CuO) particles in an aqueous copper sulfate (CuSO

4)

solution with additive alcohol such as methanol ethanol 2-propanol and ethylene glycol has been studied by X-ray exposurefrom synchrotron radiation An attenuated X-ray radiation time of 5min allows for the synthesis of Cu Cu

4O3 Cu2O and CuO

nanomicroscale particles and their aggregation into clusters The morphology and composition of the synthesized Cucupricoxide particle clusters were characterized by scanning electron microscopy scanning transmission electron microscopy and high-resolution transmission electron microscopy with energy dispersive X-ray spectroscopy Micro-Raman spectroscopy revealed thatthe clusters comprised cupric oxide core particles coveredwithCuparticlesNeitherCucupric oxide particles nor their clusterswereformed without any alcohol additives The effect of alcohol additives is attributed to the following sequential steps photochemicalreaction due to X-ray irradiation induces nucleation of the particles accompanying redox reaction and forms a cluster or aggregatesby LaMer process and DLVO interactions The procedure offers a novel route to synthesize the Cucupric oxide particles andaggregates It also provides a novel additive manufacturing process or lithography of composite materials such as metal oxideand resin

1 Introduction

Nanoparticles (NPs) of which sizes are in general below100 nm are potentially interesting for applications such ascatalysis and optical devices and the nucleation and fab-rication of NPs are fundamental topics of scientific andengineering studies [1ndash5] The optical properties of noblemetal NPs have attracted considerable attention becausethese NPs exhibit extremely high absorption and scatteringcross sections due to surface plasmon resonance MetalNPs are currently synthesized by many methods such assonochemical reaction [6ndash13] chemical aqueous reductionof metal ions [14ndash16] microwave-assisted synthesis [17] andUV-visible light or laser-induced photochemical reaction

[18ndash23] In these studies the polyol reaction [24ndash28] playsa significant important role in NP synthesis Recently X-rayirradiation has also been used to generate NPs from liquidsolution and tailor NP aggregation at desired locations [29ndash36] To this end noble metal NPs are typically used forsurface enhanced Raman scattering spectroscopy (SERS) andplasmon-assisted photochemical reactions [1ndash4 37] Poten-tial applications of NPs in a nanoscale material processinghave been demonstrated in various fields such as catalysismedicine electronics ceramics pigments and cosmetics [1ndash5]

Recently copper (Cu) and copper oxide-nanostructuredmaterials have attracted considerable attention due to their

Hindawi Publishing CorporationJournal of NanomaterialsVolume 2016 Article ID 8584304 16 pageshttpdxdoiorg10115520168584304

2 Journal of Nanomaterials

fundamental importance and potential future applications[38ndash54] Cupric oxide (Cu

2O CuO) NPs are p-type semi-

conductor materials with a low band-gap energies RecentlyPoizot et al [40] used cupric oxide NPs as anodes for lithiumion cells Izaki et al [47] produced solar cell plates consistingof Cu2OandZnONPs In addition the cupric oxideNPs have

sufficient space to absorb harmful gases Zhang et al demon-strated the application of copper oxide NPs as a gas sensor[51] Thus copper oxide NPs have additional noteworthyproperties such as nontoxicity environmental friendlinesshigh stability and recyclability Many reports have providedmethods to synthesize and characterize cupric oxide (Cu

2O

CuO) NPs [38ndash54] For example CuO NPs were prepared byBrookshier et al using a spin-coating technique to controlSiO2size [54] and Volanti et al synthesized CuO flower-like

nanostructures using a domestic hydrothermal microwave[38] Clay and Cohen synthesized CuO nanoclusters withinfilms of diblock copolymers [52] whereas Lisiecki and Pileniproduced Cu and CuO NPs from inverse micelle solutions[53]

Radiolysis using synchrotron radiation (SR) has recentlybeen investigated as a radiation-assisted method for thesynthesis of NPs [29ndash36] Due to the higher brilliance andcontrollability of X-ray from SR the X-ray radiolysis hasattracted much attention To date the synchrotron X-raysynthesis of Au Fe Ni and AuPt alloyed NPs has beenreported [29ndash36] Thus the syntheses of various metallicNPs by X-ray irradiation have been investigated A fewstudies have reported the synthesis of Cu Cu

2O Cu

4O3 and

CuO materials using X-ray irradiation from SR RecentlyOyanagi et al [55] and Yamaguchi et al [56] succeeded inproducing Cu particles by exposing diverse copper solutionsOyanagi et al [55] used Cu(II) bis(111555-hexafluoro-24pentanedionate) solution with benzopinacol C

26H22O2

octylamine C8H19N and diethylene glycol diethyl ether

while Yamaguchi et al [56] succeeded in producing Cu NPsby exposing copper sulfate (CuSO

4) liquid solution mixed

with ethanol to X-rays In the previous study we simplydemonstrated the synthesis of Cu NPs without any detailedanalysis Investigating the formation of Cu and cupric oxideNPs is required to understand the physical and chemicalmechanisms and to develop engineering applications such aslithium ion cells [51] gas sensors [57] and solar cell plates[58]

In this paper synchrotron X-ray radiation is used tosynthesize cupric oxide and Cu particles from cupric sulfatesolutions containing methanol ethanol 2-propanol andethylene glycol Here we investigate additive alcohol typedependence of cupric particles synthesized by X-ray irradia-tion High-resolution scanning electron microscope (SEM)scanning transmission electron microscope (STEM) andhigh-resolution transmission electronmicroscope (HRTEM)image with energy dispersive X-ray spectroscopy (EDX)are used to obtain a deeper understanding of the for-mation mechanism We also employ microscopic Ramanspectroscopy to characterize the cupric particles obtained byX-ray irradiation

Table 1 Summary of solutions prepared for X-ray irradiationexperiments

Prepared solution(18120583L siphoned offfrom the mixedsolution)

Base solution ampamount

Additive material ampamount

Solution 1 10 CuSO4solution

200 120583L mdash

Solution 2 10 CuSO4solution

200 120583LMethanol (CH

3COH)

10120583L

Solution 3 10 CuSO4solution

200 120583L

Ethanol(CH3CH2OH)

10120583L

Solution 4 10 CuSO4solution

200 120583L

2-Propanol(CH3CH(CH

3)OH)

10120583L

Solution 5 10 CuSO4solution

500 120583L

Ethylene glycol(HOCH

2CH2OH)

05 120583L

2 Experimental

The stock solution was prepared by dissolving 186 g ofCuSO

4sdot5H2O (Wako Chemical 9999) in 100mL of doubly

distilled water A 100mL aliquot of 10 CuSO4aqueous solu-

tion (solution 1) was prepared by diluting the stock solutionWe siphoned off 200120583L 10 CuSO

4aqueous solution into

a microtube and added 10 120583L ethanol to obtain the mixedsolution (solution 3) In the similar way other additivessuch as methanol (solution 2) and 2-propanol (solution 4)were also added into 10 CuSO

4aqueous solution In the

case of X-ray irradiation experiment with ethylene glycol themix ratio of CuSO

4solution and ethylene glycol is 500120583L to

05 120583L (solution 5) We took off 18 120583L of the mixed solution(including the CuSO

4and ethanol) and added it into the

X-ray irradiation system The prepared solutions for X-rayirradiation experiments are summarized in Table 1

The particles deposition experiments using the SR wereperformed on BL8S1 at the Aichi Synchrotron RadiationCenter (Aichi SRC) The experimental setup is schematicallyshown in Figure 1 [36 56] The X-ray spectra evaluated bythe calculation are also shown in the inset of Figure 1(a) Asdescribed in the previous work [36 56] a silicon substrate(10 times 10 times 05mm3) was dipped into the solution preparedas shown in Table 1 (total amount of 18120583L) The Si sub-strate dipped in the solution was sealed by a 2 120583m thickSiN membrane and polytetrafluoroethylene (PTFE) platesas shown in Figure 1(a) The sealed package including Sisubstrate dipped in the solution was fixed by the special steelused stainless (SUS) holder as schematically illustrated inFigure 1(a) In addition a filtered patterned X-raymaskmadeof SUS was attached on the SUS holder to obtain the contrastby X-ray irradiation The use of the X-ray mask allows usto easily get more about tenfold difference of the photonnumber in an area directly irradiated by X-ray with respectto the area covered with the X-ray mask as shown in thespectra of Figure 1(a) The X-ray mask has some hole-arrayswith various size through-holes We chose the hole-array

Journal of Nanomaterials 3

C D

F

PTFE sealSUS mask

Metallic nanoparticles

Sodium sulfate electroplating solution

Si or glass substrate

Si

Photon energy (keV)5 10 15 20

AC

D

E

B

F

E

AC

D

E

B

F

1013

1012

1011

1010

109

Phot

ons

sec

mra

d201

BW

White X-ray (1~10KeV)

Al film(thickness 500120583m)

SiN membrane(thickness 2120583m)

07~1mm

(a)

Hole array

SUS mask(thickness 180120583m)

120583m120601300

(b)

Figure 1 (a) Schematic of experimental setup for the X-ray irradiation of liquid solutionThe inset shows X-ray spectraThe evaluated photonintensity obtained from (A) synchrotron radiation at BL8S1 of Aichi SRC (B) Pt mirror (incident angle 02∘) (C) 400 120583m thick Be film (D)500 120583m thick Al film (E) metallic solution through air (1m distance) and (F) 180 120583m thick steel used stainless (SUS) mask (b) Photographof specimen with the SUS mask

consisting of through-hole with diameter of 300120583m Thespecimen prepared for the X-ray irradiation was placed onthe irradiation system After exposure to synchrotron X-rayswe washed the specimen using deionization water to removeresidual dross except particles The particles synthesizedonto the silicon substrate were observed by field emissionscanning electron microscopy (FE-SEM JEOL JSM-7001F)with EDX to perform the element analysis To prepare thecross-sectional sample for transmission electron microscope(TEM) observation we fixed the sample on TEMobservationgrid consisting of Al and Mo using a resin A focused ionbeam (FIB) was used to expose the cross-sectional surfaceof the sample to observe the TEM image We obtained thecross-sectional images and elementalmaps of the synthesizedparticles using TEM (JEOL JEM-2100F) with EDX (JEOLJED-2300T amp Gatan GIF Quantum ER) Micro-Ramanmeasurements (JASCONRS-5100)were performed using the532 nm wavelength as the excitation source The power wasmaintained at 32mW and a field lens with amagnification of100x was used The diameter of the laser spot is about 1 120583mAll experiments were performed at room temperature and inthe atmosphere

3 Results and Discussion

When the silicon substrate with only CuSO4solution with

no additives (solution 1) was exposed to X-rays no particleswere synthesized particles and clusters were only generatedin the presence of ethanol (solution 3) Figure 2 shows theSEM image after a 10 CuSO

4containing ethanol (solution

3) was irradiated with X-rays for 5min Here the X-raywas attenuated by 500 120583m thick Al foil as shown in Figure 1[36 56] As shown in Figure 2(a) a slit pattern is well definedWhen magnified the slit patterns were found to containparticles The magnified SEM images of small particles andaggregates are represented in Figures 2(b)ndash2(d) showing thatthey are not detached from the Si substrate even after washingbecause of strong van der Waals interaction

To confirm the composition of the synthesized particleselementary analysis was carried out by EDX The inset ofthe magnified SEM image in Figure 3(a) represents that thepositions at which EDX are measured The red squares cor-respond to the areas measured by EDX Signals of elementsC Cu and Si are observed in the spectra in Figures 3(a) and3(c) while an enlarged signal of O is seen in Figure 3(b)The CuO ratios in Figures 3(a)ndash3(c) are roughly estimatedto be about 905 72 and 905 respectively Here the EDXpeak of Si is derived from the silicon substrate because thesynthesized particles are small enough to pick up the Sielementary information as the background signal As a resultthese spectra suggest that the core particle is different fromthe additional particles which attach on it Carbon (C) is inthe all particles while sulfur (S) is not included in them C isconsidered to be derived from contamination or the additiveethanol C from ethanol is expected to play an importantrole in the nucleation process in which the added ethanolfacilitates the redox reaction and nucleates the Cu and cupricoxide particles [38]

To investigate the morphology and composition STEMwas performed and elemental maps were collected using

4 Journal of Nanomaterials

400120583m

(a)

10120583m

(b)

1120583m

(c)

1120583m

(d)

Figure 2 (a) SEM image of a well-patterned CuSO4solution with ethanol (solution 3) after X-ray irradiation for 5min The dashed circle

and arrows correspond to the slit patterned areas (b) Magnified SEM image of Cu particles nucleated from the mixed solution under X-rayirradiation ((c) and (d)) High-resolution SEM images of the nucleated particles The arrow in (c) points out a cuboctahedral like particle

(c)

(i)(ii)

(iii)

1 2 3 4 5 6 7 8 9Energy (keV)

CO Si SCu

Cu

Cu

(b)

1 3 5 7 9

(a)

Energy (keV)2 4 6 8

Cou

nt (a

rb u

nit)C

ount

(arb

uni

t)

Cou

nt (a

rb u

nit)

O

Cu

CuCu

Cu

CuCu

Si

Si

O

(i)

(ii)

(iii)

1120583m

Figure 3 In the inset of (a) three red squared frames (i) (ii) and (iii) on the high-resolution SEM image of the particle depict the EDXmeasurement positions EDX spectra measured from the positions (i) (ii) and (iii) are shown in (a) (b) and (c) respectively The position(ii) corresponds to the surface of the core particle while the positions (i) and (iii) are the surfaces of attached particles

Journal of Nanomaterials 5

Cu K120572

0 2 4 6 8 10Energy (keV)

Cou

nt (a

rb u

nit)

C K120572

O K120572

Si K120572

(a)

SEM2120583m

(b)

2120583m2120583m Cu K120572

(c)

O K1205722120583m

(d)

Si K1205722120583m

(e)

C K1205722120583m

(f)

Figure 4 (a) EDX spectrum of the observed cross-sectional area shown in secondary-electron topographical TEM image of (b) (c)ndash(f)Elemental mappings of Cu O Si and C respectively

EDX Figure 4(a) shows the EDX spectrum of the cross-sectional area of a cluster generated by X-ray irradiation inthe liquid solution shown in Figure 4(b) which is the STEMimageThe spectra includes necessary elemental informationalong with nonessential signals derived from the TEM gridmount materials (C Al Si andMo) and a Ga signal from thefocused ion beam (FIB) milling process In this manuscriptexcept the carbon C elementary maps of Al Mo and Gaare not shown to avoid cumbersome maps of which providenonessential phenomena Figures 4(c)ndash4(f) show the elemen-tarymaps of CuO Si andC respectively the bright and darkcontrasts correspond to high and low elemental abundancerespectively Note that the elements Si and C remained fromthe polishing agent slurry and mold resin respectively afterFIB milling Thus both elements reside around the particlesnear the TEM grid frame as shown in Figures 4(e) and 4(f)This cross-sectional TEM elementary mapping indicates thatall synthesized particles are at least including Cu as shown inFigure 4(c) and the element C does not play an important rolein the ripping process of the particles By comparison withFigures 4(c) and 4(d) the amount of oxygen (O) is higherincluded in the core particle while oxygen distribution isbarely visible in the small particles attached on the coreparticle (Figure 4(d)) One can see the single crystalline-likestructure in all synthesized particles because we recognized

the several facets in morphology observation using TEM andSEM

To understand the details of the elementary distributionsin the synthesized particles the magnified STEM imagesand EDX mappings are shown in Figure 5 Figure 5(a)shows the topographical STEM image of the cross sectionof the aggregate Figures 5(b) and 5(c) show the EDXelementary mappings of Cu (red-colored) and O (orange-colored) respectively The elemental mappings clearly showanisotropic distributions of Cu and O O is almost detectedin the original single crystalline core region whereas Cu ismainly found in all particles similarly to the results shown inFigures 4 and 5

Furthermore we collected the micro-Raman spectra inorder to reveal crystallographic informationThe photographinsets of Figure 6 show the respective aggregates consistingsome particles The labels (A) (C) and (D) correspond tothe measurement positions of micro-Raman spectroscopiesThe bright green positions correspond to the areas irradiatedby the excitation laser Figures 6(a)ndash6(d) show the micro-Raman spectra of (a) surface of metallic particle (b) siliconsubstrate (c) surface of core particle and (d) particle on thecore particle respectively The micro-Raman spectrometer isso sensitive that it can pick up the information at focal depthof about 500 nmAs shown in Figures 6(a) and 6(d) the broad

6 Journal of Nanomaterials

250nm SEM(a)

250nm Cu K120572(b)

250nm O K120572(c)

Figure 5 (a) High-resolution TEM topographical image of the aggregate cross section ((b) and (c)) Elementary mappings of Cu and Orespectively

spectra are observed indicating that the particles attachingon core particle aremetal and are deduced that the nucleationgrowth or aggregate of Cu particles occurred

Next we focus on the spectrum of Figure 6(c) The peaksat 277 324 520 and 613 cmminus1 appeared clearly in Figure 6(c)These peaks are possibly attributed to summation of threecupric oxides Cu

2O CuO and Cu

4O3[38 39] Although a

comparison of Raman spectra shown in Figures 6(a) 6(c)and 6(d) with that of the Si substrate in Figure 6(b) indicatesthat the peak at 520 cmminus1 is attributed to the Si substratethere remains the undeniable possibility that the peak at520 cmminus1 is derived from A

1g mode of Cu4O3because the

particle volume is thick enough to shade the excitation laserreaching Si substrate Accordingly to the previous studiesof Debbichi et al [39] and Volanti et al [38] our observedRaman signals at 277 324 and 613 cmminus1 from the core particlecorrespond to Raman signals from Ag (2838 cmminus1) and Bg(3335 and 6225 cmminus1) modes of CuO respectively [38 39]In this study the corresponding Raman shifts are a little bitlower than those reported in [40 41] As shown in the insetphotograph of Figure 6(d) after the measurement of Ramanspectra the particles that the laser had been focused on wereslightly melted It is attributed that a red shift was inducedby the heating effect from laser excitation In addition weunderstand the potential of the broad Raman peak structureranging from 500 to 630 cmminus1 being originated from Cu

2O

[38 39] The result may be explainable for CuO (at ) ratiosof the aggregates by comparing with EDX measurementshowever in the present stage it allows us to deduce that thesynthesized particle is expected to be a composited cupricoxide consisting of CuO Cu

2O and Cu

4O3 while some

particles attached to the core particle were deduced to beCu particles Thus in either case we demonstrated one-stepsynthesis of Cucupric oxide and the aggregates induced fromthe liquid solution by direct X-ray irradiation

Various investigations were performed to understandthe mechanism of particle formation based on the inter-action of sonochemical preparation [6ndash13] laser light [18ndash23] microwave irradiation [14ndash17 38 39 41ndash51] and X-ray

and 120574-ray irradiation (radiolysis) [29ndash36 55 56] For pho-tochemical reactions both thermal and electronic excitationeffects were considered and discussed To our knowledge noreport has discussed the particle formation mechanism fromCuSO

4solution under X-ray irradiation Therefore we have

attempted to understand the phenomenological chemicalreaction process

In our experiment hydrated electrons hydroxyl radicalsand hydrogen atomswere the reactive intermediates in the X-ray irradiation of themixed aqueous solution As described inprevious studies the X-ray irradiation from SR provides theproton radical and hydroxyl radical as the following [59ndash65]

H2O

X-ray997888997888997888997888rarr eminusaq

∙H ∙OHH2O2H2 (1)

As described above in this study the X-ray irradiation ofonly CuSO

4solution (without ethanol) did not result in

the formation of any particles This is because the protonand hydroxyl radicals provided by X-ray irradiation are notsufficient to form copper particles via reduction due to thehydration

Upon the addition of an alcohol (eg methanol andethanol) the ∙OH and ∙H radicals are scavenged to yieldreducing organic radicals In the case where ethanol is addedto the solution proton and hydroxyl radicals react as follows[59ndash65]

∙OH (∙H) + CH3CH2OH 997888rarr H2O (H2) + ∙CH

2OH (2a)

CH3CH2OH

X-ray997888997888997888997888rarr CH

3CHO + 2eminus + 2H+ (2b)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr [(CH

3CH2OH)+119899]lowast

+ eminus (2c)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr

(CH3CH2OH)119899minus1

H+ + CH3CHO + eminus

(2d)

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

2 Journal of Nanomaterials

fundamental importance and potential future applications[38ndash54] Cupric oxide (Cu

2O CuO) NPs are p-type semi-

conductor materials with a low band-gap energies RecentlyPoizot et al [40] used cupric oxide NPs as anodes for lithiumion cells Izaki et al [47] produced solar cell plates consistingof Cu2OandZnONPs In addition the cupric oxideNPs have

sufficient space to absorb harmful gases Zhang et al demon-strated the application of copper oxide NPs as a gas sensor[51] Thus copper oxide NPs have additional noteworthyproperties such as nontoxicity environmental friendlinesshigh stability and recyclability Many reports have providedmethods to synthesize and characterize cupric oxide (Cu

2O

CuO) NPs [38ndash54] For example CuO NPs were prepared byBrookshier et al using a spin-coating technique to controlSiO2size [54] and Volanti et al synthesized CuO flower-like

nanostructures using a domestic hydrothermal microwave[38] Clay and Cohen synthesized CuO nanoclusters withinfilms of diblock copolymers [52] whereas Lisiecki and Pileniproduced Cu and CuO NPs from inverse micelle solutions[53]

Radiolysis using synchrotron radiation (SR) has recentlybeen investigated as a radiation-assisted method for thesynthesis of NPs [29ndash36] Due to the higher brilliance andcontrollability of X-ray from SR the X-ray radiolysis hasattracted much attention To date the synchrotron X-raysynthesis of Au Fe Ni and AuPt alloyed NPs has beenreported [29ndash36] Thus the syntheses of various metallicNPs by X-ray irradiation have been investigated A fewstudies have reported the synthesis of Cu Cu

2O Cu

4O3 and

CuO materials using X-ray irradiation from SR RecentlyOyanagi et al [55] and Yamaguchi et al [56] succeeded inproducing Cu particles by exposing diverse copper solutionsOyanagi et al [55] used Cu(II) bis(111555-hexafluoro-24pentanedionate) solution with benzopinacol C

26H22O2

octylamine C8H19N and diethylene glycol diethyl ether

while Yamaguchi et al [56] succeeded in producing Cu NPsby exposing copper sulfate (CuSO

4) liquid solution mixed

with ethanol to X-rays In the previous study we simplydemonstrated the synthesis of Cu NPs without any detailedanalysis Investigating the formation of Cu and cupric oxideNPs is required to understand the physical and chemicalmechanisms and to develop engineering applications such aslithium ion cells [51] gas sensors [57] and solar cell plates[58]

In this paper synchrotron X-ray radiation is used tosynthesize cupric oxide and Cu particles from cupric sulfatesolutions containing methanol ethanol 2-propanol andethylene glycol Here we investigate additive alcohol typedependence of cupric particles synthesized by X-ray irradia-tion High-resolution scanning electron microscope (SEM)scanning transmission electron microscope (STEM) andhigh-resolution transmission electronmicroscope (HRTEM)image with energy dispersive X-ray spectroscopy (EDX)are used to obtain a deeper understanding of the for-mation mechanism We also employ microscopic Ramanspectroscopy to characterize the cupric particles obtained byX-ray irradiation

Table 1 Summary of solutions prepared for X-ray irradiationexperiments

Prepared solution(18120583L siphoned offfrom the mixedsolution)

Base solution ampamount

Additive material ampamount

Solution 1 10 CuSO4solution

200 120583L mdash

Solution 2 10 CuSO4solution

200 120583LMethanol (CH

3COH)

10120583L

Solution 3 10 CuSO4solution

200 120583L

Ethanol(CH3CH2OH)

10120583L

Solution 4 10 CuSO4solution

200 120583L

2-Propanol(CH3CH(CH

3)OH)

10120583L

Solution 5 10 CuSO4solution

500 120583L

Ethylene glycol(HOCH

2CH2OH)

05 120583L

2 Experimental

The stock solution was prepared by dissolving 186 g ofCuSO

4sdot5H2O (Wako Chemical 9999) in 100mL of doubly

distilled water A 100mL aliquot of 10 CuSO4aqueous solu-

tion (solution 1) was prepared by diluting the stock solutionWe siphoned off 200120583L 10 CuSO

4aqueous solution into

a microtube and added 10 120583L ethanol to obtain the mixedsolution (solution 3) In the similar way other additivessuch as methanol (solution 2) and 2-propanol (solution 4)were also added into 10 CuSO

4aqueous solution In the

case of X-ray irradiation experiment with ethylene glycol themix ratio of CuSO

4solution and ethylene glycol is 500120583L to

05 120583L (solution 5) We took off 18 120583L of the mixed solution(including the CuSO

4and ethanol) and added it into the

X-ray irradiation system The prepared solutions for X-rayirradiation experiments are summarized in Table 1

The particles deposition experiments using the SR wereperformed on BL8S1 at the Aichi Synchrotron RadiationCenter (Aichi SRC) The experimental setup is schematicallyshown in Figure 1 [36 56] The X-ray spectra evaluated bythe calculation are also shown in the inset of Figure 1(a) Asdescribed in the previous work [36 56] a silicon substrate(10 times 10 times 05mm3) was dipped into the solution preparedas shown in Table 1 (total amount of 18120583L) The Si sub-strate dipped in the solution was sealed by a 2 120583m thickSiN membrane and polytetrafluoroethylene (PTFE) platesas shown in Figure 1(a) The sealed package including Sisubstrate dipped in the solution was fixed by the special steelused stainless (SUS) holder as schematically illustrated inFigure 1(a) In addition a filtered patterned X-raymaskmadeof SUS was attached on the SUS holder to obtain the contrastby X-ray irradiation The use of the X-ray mask allows usto easily get more about tenfold difference of the photonnumber in an area directly irradiated by X-ray with respectto the area covered with the X-ray mask as shown in thespectra of Figure 1(a) The X-ray mask has some hole-arrayswith various size through-holes We chose the hole-array

Journal of Nanomaterials 3

C D

F

PTFE sealSUS mask

Metallic nanoparticles

Sodium sulfate electroplating solution

Si or glass substrate

Si

Photon energy (keV)5 10 15 20

AC

D

E

B

F

E

AC

D

E

B

F

1013

1012

1011

1010

109

Phot

ons

sec

mra

d201

BW

White X-ray (1~10KeV)

Al film(thickness 500120583m)

SiN membrane(thickness 2120583m)

07~1mm

(a)

Hole array

SUS mask(thickness 180120583m)

120583m120601300

(b)

Figure 1 (a) Schematic of experimental setup for the X-ray irradiation of liquid solutionThe inset shows X-ray spectraThe evaluated photonintensity obtained from (A) synchrotron radiation at BL8S1 of Aichi SRC (B) Pt mirror (incident angle 02∘) (C) 400 120583m thick Be film (D)500 120583m thick Al film (E) metallic solution through air (1m distance) and (F) 180 120583m thick steel used stainless (SUS) mask (b) Photographof specimen with the SUS mask

consisting of through-hole with diameter of 300120583m Thespecimen prepared for the X-ray irradiation was placed onthe irradiation system After exposure to synchrotron X-rayswe washed the specimen using deionization water to removeresidual dross except particles The particles synthesizedonto the silicon substrate were observed by field emissionscanning electron microscopy (FE-SEM JEOL JSM-7001F)with EDX to perform the element analysis To prepare thecross-sectional sample for transmission electron microscope(TEM) observation we fixed the sample on TEMobservationgrid consisting of Al and Mo using a resin A focused ionbeam (FIB) was used to expose the cross-sectional surfaceof the sample to observe the TEM image We obtained thecross-sectional images and elementalmaps of the synthesizedparticles using TEM (JEOL JEM-2100F) with EDX (JEOLJED-2300T amp Gatan GIF Quantum ER) Micro-Ramanmeasurements (JASCONRS-5100)were performed using the532 nm wavelength as the excitation source The power wasmaintained at 32mW and a field lens with amagnification of100x was used The diameter of the laser spot is about 1 120583mAll experiments were performed at room temperature and inthe atmosphere

3 Results and Discussion

When the silicon substrate with only CuSO4solution with

no additives (solution 1) was exposed to X-rays no particleswere synthesized particles and clusters were only generatedin the presence of ethanol (solution 3) Figure 2 shows theSEM image after a 10 CuSO

4containing ethanol (solution

3) was irradiated with X-rays for 5min Here the X-raywas attenuated by 500 120583m thick Al foil as shown in Figure 1[36 56] As shown in Figure 2(a) a slit pattern is well definedWhen magnified the slit patterns were found to containparticles The magnified SEM images of small particles andaggregates are represented in Figures 2(b)ndash2(d) showing thatthey are not detached from the Si substrate even after washingbecause of strong van der Waals interaction

To confirm the composition of the synthesized particleselementary analysis was carried out by EDX The inset ofthe magnified SEM image in Figure 3(a) represents that thepositions at which EDX are measured The red squares cor-respond to the areas measured by EDX Signals of elementsC Cu and Si are observed in the spectra in Figures 3(a) and3(c) while an enlarged signal of O is seen in Figure 3(b)The CuO ratios in Figures 3(a)ndash3(c) are roughly estimatedto be about 905 72 and 905 respectively Here the EDXpeak of Si is derived from the silicon substrate because thesynthesized particles are small enough to pick up the Sielementary information as the background signal As a resultthese spectra suggest that the core particle is different fromthe additional particles which attach on it Carbon (C) is inthe all particles while sulfur (S) is not included in them C isconsidered to be derived from contamination or the additiveethanol C from ethanol is expected to play an importantrole in the nucleation process in which the added ethanolfacilitates the redox reaction and nucleates the Cu and cupricoxide particles [38]

To investigate the morphology and composition STEMwas performed and elemental maps were collected using

4 Journal of Nanomaterials

400120583m

(a)

10120583m

(b)

1120583m

(c)

1120583m

(d)

Figure 2 (a) SEM image of a well-patterned CuSO4solution with ethanol (solution 3) after X-ray irradiation for 5min The dashed circle

and arrows correspond to the slit patterned areas (b) Magnified SEM image of Cu particles nucleated from the mixed solution under X-rayirradiation ((c) and (d)) High-resolution SEM images of the nucleated particles The arrow in (c) points out a cuboctahedral like particle

(c)

(i)(ii)

(iii)

1 2 3 4 5 6 7 8 9Energy (keV)

CO Si SCu

Cu

Cu

(b)

1 3 5 7 9

(a)

Energy (keV)2 4 6 8

Cou

nt (a

rb u

nit)C

ount

(arb

uni

t)

Cou

nt (a

rb u

nit)

O

Cu

CuCu

Cu

CuCu

Si

Si

O

(i)

(ii)

(iii)

1120583m

Figure 3 In the inset of (a) three red squared frames (i) (ii) and (iii) on the high-resolution SEM image of the particle depict the EDXmeasurement positions EDX spectra measured from the positions (i) (ii) and (iii) are shown in (a) (b) and (c) respectively The position(ii) corresponds to the surface of the core particle while the positions (i) and (iii) are the surfaces of attached particles

Journal of Nanomaterials 5

Cu K120572

0 2 4 6 8 10Energy (keV)

Cou

nt (a

rb u

nit)

C K120572

O K120572

Si K120572

(a)

SEM2120583m

(b)

2120583m2120583m Cu K120572

(c)

O K1205722120583m

(d)

Si K1205722120583m

(e)

C K1205722120583m

(f)

Figure 4 (a) EDX spectrum of the observed cross-sectional area shown in secondary-electron topographical TEM image of (b) (c)ndash(f)Elemental mappings of Cu O Si and C respectively

EDX Figure 4(a) shows the EDX spectrum of the cross-sectional area of a cluster generated by X-ray irradiation inthe liquid solution shown in Figure 4(b) which is the STEMimageThe spectra includes necessary elemental informationalong with nonessential signals derived from the TEM gridmount materials (C Al Si andMo) and a Ga signal from thefocused ion beam (FIB) milling process In this manuscriptexcept the carbon C elementary maps of Al Mo and Gaare not shown to avoid cumbersome maps of which providenonessential phenomena Figures 4(c)ndash4(f) show the elemen-tarymaps of CuO Si andC respectively the bright and darkcontrasts correspond to high and low elemental abundancerespectively Note that the elements Si and C remained fromthe polishing agent slurry and mold resin respectively afterFIB milling Thus both elements reside around the particlesnear the TEM grid frame as shown in Figures 4(e) and 4(f)This cross-sectional TEM elementary mapping indicates thatall synthesized particles are at least including Cu as shown inFigure 4(c) and the element C does not play an important rolein the ripping process of the particles By comparison withFigures 4(c) and 4(d) the amount of oxygen (O) is higherincluded in the core particle while oxygen distribution isbarely visible in the small particles attached on the coreparticle (Figure 4(d)) One can see the single crystalline-likestructure in all synthesized particles because we recognized

the several facets in morphology observation using TEM andSEM

To understand the details of the elementary distributionsin the synthesized particles the magnified STEM imagesand EDX mappings are shown in Figure 5 Figure 5(a)shows the topographical STEM image of the cross sectionof the aggregate Figures 5(b) and 5(c) show the EDXelementary mappings of Cu (red-colored) and O (orange-colored) respectively The elemental mappings clearly showanisotropic distributions of Cu and O O is almost detectedin the original single crystalline core region whereas Cu ismainly found in all particles similarly to the results shown inFigures 4 and 5

Furthermore we collected the micro-Raman spectra inorder to reveal crystallographic informationThe photographinsets of Figure 6 show the respective aggregates consistingsome particles The labels (A) (C) and (D) correspond tothe measurement positions of micro-Raman spectroscopiesThe bright green positions correspond to the areas irradiatedby the excitation laser Figures 6(a)ndash6(d) show the micro-Raman spectra of (a) surface of metallic particle (b) siliconsubstrate (c) surface of core particle and (d) particle on thecore particle respectively The micro-Raman spectrometer isso sensitive that it can pick up the information at focal depthof about 500 nmAs shown in Figures 6(a) and 6(d) the broad

6 Journal of Nanomaterials

250nm SEM(a)

250nm Cu K120572(b)

250nm O K120572(c)

Figure 5 (a) High-resolution TEM topographical image of the aggregate cross section ((b) and (c)) Elementary mappings of Cu and Orespectively

spectra are observed indicating that the particles attachingon core particle aremetal and are deduced that the nucleationgrowth or aggregate of Cu particles occurred

Next we focus on the spectrum of Figure 6(c) The peaksat 277 324 520 and 613 cmminus1 appeared clearly in Figure 6(c)These peaks are possibly attributed to summation of threecupric oxides Cu

2O CuO and Cu

4O3[38 39] Although a

comparison of Raman spectra shown in Figures 6(a) 6(c)and 6(d) with that of the Si substrate in Figure 6(b) indicatesthat the peak at 520 cmminus1 is attributed to the Si substratethere remains the undeniable possibility that the peak at520 cmminus1 is derived from A

1g mode of Cu4O3because the

particle volume is thick enough to shade the excitation laserreaching Si substrate Accordingly to the previous studiesof Debbichi et al [39] and Volanti et al [38] our observedRaman signals at 277 324 and 613 cmminus1 from the core particlecorrespond to Raman signals from Ag (2838 cmminus1) and Bg(3335 and 6225 cmminus1) modes of CuO respectively [38 39]In this study the corresponding Raman shifts are a little bitlower than those reported in [40 41] As shown in the insetphotograph of Figure 6(d) after the measurement of Ramanspectra the particles that the laser had been focused on wereslightly melted It is attributed that a red shift was inducedby the heating effect from laser excitation In addition weunderstand the potential of the broad Raman peak structureranging from 500 to 630 cmminus1 being originated from Cu

2O

[38 39] The result may be explainable for CuO (at ) ratiosof the aggregates by comparing with EDX measurementshowever in the present stage it allows us to deduce that thesynthesized particle is expected to be a composited cupricoxide consisting of CuO Cu

2O and Cu

4O3 while some

particles attached to the core particle were deduced to beCu particles Thus in either case we demonstrated one-stepsynthesis of Cucupric oxide and the aggregates induced fromthe liquid solution by direct X-ray irradiation

Various investigations were performed to understandthe mechanism of particle formation based on the inter-action of sonochemical preparation [6ndash13] laser light [18ndash23] microwave irradiation [14ndash17 38 39 41ndash51] and X-ray

and 120574-ray irradiation (radiolysis) [29ndash36 55 56] For pho-tochemical reactions both thermal and electronic excitationeffects were considered and discussed To our knowledge noreport has discussed the particle formation mechanism fromCuSO

4solution under X-ray irradiation Therefore we have

attempted to understand the phenomenological chemicalreaction process

In our experiment hydrated electrons hydroxyl radicalsand hydrogen atomswere the reactive intermediates in the X-ray irradiation of themixed aqueous solution As described inprevious studies the X-ray irradiation from SR provides theproton radical and hydroxyl radical as the following [59ndash65]

H2O

X-ray997888997888997888997888rarr eminusaq

∙H ∙OHH2O2H2 (1)

As described above in this study the X-ray irradiation ofonly CuSO

4solution (without ethanol) did not result in

the formation of any particles This is because the protonand hydroxyl radicals provided by X-ray irradiation are notsufficient to form copper particles via reduction due to thehydration

Upon the addition of an alcohol (eg methanol andethanol) the ∙OH and ∙H radicals are scavenged to yieldreducing organic radicals In the case where ethanol is addedto the solution proton and hydroxyl radicals react as follows[59ndash65]

∙OH (∙H) + CH3CH2OH 997888rarr H2O (H2) + ∙CH

2OH (2a)

CH3CH2OH

X-ray997888997888997888997888rarr CH

3CHO + 2eminus + 2H+ (2b)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr [(CH

3CH2OH)+119899]lowast

+ eminus (2c)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr

(CH3CH2OH)119899minus1

H+ + CH3CHO + eminus

(2d)

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 3

C D

F

PTFE sealSUS mask

Metallic nanoparticles

Sodium sulfate electroplating solution

Si or glass substrate

Si

Photon energy (keV)5 10 15 20

AC

D

E

B

F

E

AC

D

E

B

F

1013

1012

1011

1010

109

Phot

ons

sec

mra

d201

BW

White X-ray (1~10KeV)

Al film(thickness 500120583m)

SiN membrane(thickness 2120583m)

07~1mm

(a)

Hole array

SUS mask(thickness 180120583m)

120583m120601300

(b)

Figure 1 (a) Schematic of experimental setup for the X-ray irradiation of liquid solutionThe inset shows X-ray spectraThe evaluated photonintensity obtained from (A) synchrotron radiation at BL8S1 of Aichi SRC (B) Pt mirror (incident angle 02∘) (C) 400 120583m thick Be film (D)500 120583m thick Al film (E) metallic solution through air (1m distance) and (F) 180 120583m thick steel used stainless (SUS) mask (b) Photographof specimen with the SUS mask

consisting of through-hole with diameter of 300120583m Thespecimen prepared for the X-ray irradiation was placed onthe irradiation system After exposure to synchrotron X-rayswe washed the specimen using deionization water to removeresidual dross except particles The particles synthesizedonto the silicon substrate were observed by field emissionscanning electron microscopy (FE-SEM JEOL JSM-7001F)with EDX to perform the element analysis To prepare thecross-sectional sample for transmission electron microscope(TEM) observation we fixed the sample on TEMobservationgrid consisting of Al and Mo using a resin A focused ionbeam (FIB) was used to expose the cross-sectional surfaceof the sample to observe the TEM image We obtained thecross-sectional images and elementalmaps of the synthesizedparticles using TEM (JEOL JEM-2100F) with EDX (JEOLJED-2300T amp Gatan GIF Quantum ER) Micro-Ramanmeasurements (JASCONRS-5100)were performed using the532 nm wavelength as the excitation source The power wasmaintained at 32mW and a field lens with amagnification of100x was used The diameter of the laser spot is about 1 120583mAll experiments were performed at room temperature and inthe atmosphere

3 Results and Discussion

When the silicon substrate with only CuSO4solution with

no additives (solution 1) was exposed to X-rays no particleswere synthesized particles and clusters were only generatedin the presence of ethanol (solution 3) Figure 2 shows theSEM image after a 10 CuSO

4containing ethanol (solution

3) was irradiated with X-rays for 5min Here the X-raywas attenuated by 500 120583m thick Al foil as shown in Figure 1[36 56] As shown in Figure 2(a) a slit pattern is well definedWhen magnified the slit patterns were found to containparticles The magnified SEM images of small particles andaggregates are represented in Figures 2(b)ndash2(d) showing thatthey are not detached from the Si substrate even after washingbecause of strong van der Waals interaction

To confirm the composition of the synthesized particleselementary analysis was carried out by EDX The inset ofthe magnified SEM image in Figure 3(a) represents that thepositions at which EDX are measured The red squares cor-respond to the areas measured by EDX Signals of elementsC Cu and Si are observed in the spectra in Figures 3(a) and3(c) while an enlarged signal of O is seen in Figure 3(b)The CuO ratios in Figures 3(a)ndash3(c) are roughly estimatedto be about 905 72 and 905 respectively Here the EDXpeak of Si is derived from the silicon substrate because thesynthesized particles are small enough to pick up the Sielementary information as the background signal As a resultthese spectra suggest that the core particle is different fromthe additional particles which attach on it Carbon (C) is inthe all particles while sulfur (S) is not included in them C isconsidered to be derived from contamination or the additiveethanol C from ethanol is expected to play an importantrole in the nucleation process in which the added ethanolfacilitates the redox reaction and nucleates the Cu and cupricoxide particles [38]

To investigate the morphology and composition STEMwas performed and elemental maps were collected using

4 Journal of Nanomaterials

400120583m

(a)

10120583m

(b)

1120583m

(c)

1120583m

(d)

Figure 2 (a) SEM image of a well-patterned CuSO4solution with ethanol (solution 3) after X-ray irradiation for 5min The dashed circle

and arrows correspond to the slit patterned areas (b) Magnified SEM image of Cu particles nucleated from the mixed solution under X-rayirradiation ((c) and (d)) High-resolution SEM images of the nucleated particles The arrow in (c) points out a cuboctahedral like particle

(c)

(i)(ii)

(iii)

1 2 3 4 5 6 7 8 9Energy (keV)

CO Si SCu

Cu

Cu

(b)

1 3 5 7 9

(a)

Energy (keV)2 4 6 8

Cou

nt (a

rb u

nit)C

ount

(arb

uni

t)

Cou

nt (a

rb u

nit)

O

Cu

CuCu

Cu

CuCu

Si

Si

O

(i)

(ii)

(iii)

1120583m

Figure 3 In the inset of (a) three red squared frames (i) (ii) and (iii) on the high-resolution SEM image of the particle depict the EDXmeasurement positions EDX spectra measured from the positions (i) (ii) and (iii) are shown in (a) (b) and (c) respectively The position(ii) corresponds to the surface of the core particle while the positions (i) and (iii) are the surfaces of attached particles

Journal of Nanomaterials 5

Cu K120572

0 2 4 6 8 10Energy (keV)

Cou

nt (a

rb u

nit)

C K120572

O K120572

Si K120572

(a)

SEM2120583m

(b)

2120583m2120583m Cu K120572

(c)

O K1205722120583m

(d)

Si K1205722120583m

(e)

C K1205722120583m

(f)

Figure 4 (a) EDX spectrum of the observed cross-sectional area shown in secondary-electron topographical TEM image of (b) (c)ndash(f)Elemental mappings of Cu O Si and C respectively

EDX Figure 4(a) shows the EDX spectrum of the cross-sectional area of a cluster generated by X-ray irradiation inthe liquid solution shown in Figure 4(b) which is the STEMimageThe spectra includes necessary elemental informationalong with nonessential signals derived from the TEM gridmount materials (C Al Si andMo) and a Ga signal from thefocused ion beam (FIB) milling process In this manuscriptexcept the carbon C elementary maps of Al Mo and Gaare not shown to avoid cumbersome maps of which providenonessential phenomena Figures 4(c)ndash4(f) show the elemen-tarymaps of CuO Si andC respectively the bright and darkcontrasts correspond to high and low elemental abundancerespectively Note that the elements Si and C remained fromthe polishing agent slurry and mold resin respectively afterFIB milling Thus both elements reside around the particlesnear the TEM grid frame as shown in Figures 4(e) and 4(f)This cross-sectional TEM elementary mapping indicates thatall synthesized particles are at least including Cu as shown inFigure 4(c) and the element C does not play an important rolein the ripping process of the particles By comparison withFigures 4(c) and 4(d) the amount of oxygen (O) is higherincluded in the core particle while oxygen distribution isbarely visible in the small particles attached on the coreparticle (Figure 4(d)) One can see the single crystalline-likestructure in all synthesized particles because we recognized

the several facets in morphology observation using TEM andSEM

To understand the details of the elementary distributionsin the synthesized particles the magnified STEM imagesand EDX mappings are shown in Figure 5 Figure 5(a)shows the topographical STEM image of the cross sectionof the aggregate Figures 5(b) and 5(c) show the EDXelementary mappings of Cu (red-colored) and O (orange-colored) respectively The elemental mappings clearly showanisotropic distributions of Cu and O O is almost detectedin the original single crystalline core region whereas Cu ismainly found in all particles similarly to the results shown inFigures 4 and 5

Furthermore we collected the micro-Raman spectra inorder to reveal crystallographic informationThe photographinsets of Figure 6 show the respective aggregates consistingsome particles The labels (A) (C) and (D) correspond tothe measurement positions of micro-Raman spectroscopiesThe bright green positions correspond to the areas irradiatedby the excitation laser Figures 6(a)ndash6(d) show the micro-Raman spectra of (a) surface of metallic particle (b) siliconsubstrate (c) surface of core particle and (d) particle on thecore particle respectively The micro-Raman spectrometer isso sensitive that it can pick up the information at focal depthof about 500 nmAs shown in Figures 6(a) and 6(d) the broad

6 Journal of Nanomaterials

250nm SEM(a)

250nm Cu K120572(b)

250nm O K120572(c)

Figure 5 (a) High-resolution TEM topographical image of the aggregate cross section ((b) and (c)) Elementary mappings of Cu and Orespectively

spectra are observed indicating that the particles attachingon core particle aremetal and are deduced that the nucleationgrowth or aggregate of Cu particles occurred

Next we focus on the spectrum of Figure 6(c) The peaksat 277 324 520 and 613 cmminus1 appeared clearly in Figure 6(c)These peaks are possibly attributed to summation of threecupric oxides Cu

2O CuO and Cu

4O3[38 39] Although a

comparison of Raman spectra shown in Figures 6(a) 6(c)and 6(d) with that of the Si substrate in Figure 6(b) indicatesthat the peak at 520 cmminus1 is attributed to the Si substratethere remains the undeniable possibility that the peak at520 cmminus1 is derived from A

1g mode of Cu4O3because the

particle volume is thick enough to shade the excitation laserreaching Si substrate Accordingly to the previous studiesof Debbichi et al [39] and Volanti et al [38] our observedRaman signals at 277 324 and 613 cmminus1 from the core particlecorrespond to Raman signals from Ag (2838 cmminus1) and Bg(3335 and 6225 cmminus1) modes of CuO respectively [38 39]In this study the corresponding Raman shifts are a little bitlower than those reported in [40 41] As shown in the insetphotograph of Figure 6(d) after the measurement of Ramanspectra the particles that the laser had been focused on wereslightly melted It is attributed that a red shift was inducedby the heating effect from laser excitation In addition weunderstand the potential of the broad Raman peak structureranging from 500 to 630 cmminus1 being originated from Cu

2O

[38 39] The result may be explainable for CuO (at ) ratiosof the aggregates by comparing with EDX measurementshowever in the present stage it allows us to deduce that thesynthesized particle is expected to be a composited cupricoxide consisting of CuO Cu

2O and Cu

4O3 while some

particles attached to the core particle were deduced to beCu particles Thus in either case we demonstrated one-stepsynthesis of Cucupric oxide and the aggregates induced fromthe liquid solution by direct X-ray irradiation

Various investigations were performed to understandthe mechanism of particle formation based on the inter-action of sonochemical preparation [6ndash13] laser light [18ndash23] microwave irradiation [14ndash17 38 39 41ndash51] and X-ray

and 120574-ray irradiation (radiolysis) [29ndash36 55 56] For pho-tochemical reactions both thermal and electronic excitationeffects were considered and discussed To our knowledge noreport has discussed the particle formation mechanism fromCuSO

4solution under X-ray irradiation Therefore we have

attempted to understand the phenomenological chemicalreaction process

In our experiment hydrated electrons hydroxyl radicalsand hydrogen atomswere the reactive intermediates in the X-ray irradiation of themixed aqueous solution As described inprevious studies the X-ray irradiation from SR provides theproton radical and hydroxyl radical as the following [59ndash65]

H2O

X-ray997888997888997888997888rarr eminusaq

∙H ∙OHH2O2H2 (1)

As described above in this study the X-ray irradiation ofonly CuSO

4solution (without ethanol) did not result in

the formation of any particles This is because the protonand hydroxyl radicals provided by X-ray irradiation are notsufficient to form copper particles via reduction due to thehydration

Upon the addition of an alcohol (eg methanol andethanol) the ∙OH and ∙H radicals are scavenged to yieldreducing organic radicals In the case where ethanol is addedto the solution proton and hydroxyl radicals react as follows[59ndash65]

∙OH (∙H) + CH3CH2OH 997888rarr H2O (H2) + ∙CH

2OH (2a)

CH3CH2OH

X-ray997888997888997888997888rarr CH

3CHO + 2eminus + 2H+ (2b)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr [(CH

3CH2OH)+119899]lowast

+ eminus (2c)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr

(CH3CH2OH)119899minus1

H+ + CH3CHO + eminus

(2d)

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

4 Journal of Nanomaterials

400120583m

(a)

10120583m

(b)

1120583m

(c)

1120583m

(d)

Figure 2 (a) SEM image of a well-patterned CuSO4solution with ethanol (solution 3) after X-ray irradiation for 5min The dashed circle

and arrows correspond to the slit patterned areas (b) Magnified SEM image of Cu particles nucleated from the mixed solution under X-rayirradiation ((c) and (d)) High-resolution SEM images of the nucleated particles The arrow in (c) points out a cuboctahedral like particle

(c)

(i)(ii)

(iii)

1 2 3 4 5 6 7 8 9Energy (keV)

CO Si SCu

Cu

Cu

(b)

1 3 5 7 9

(a)

Energy (keV)2 4 6 8

Cou

nt (a

rb u

nit)C

ount

(arb

uni

t)

Cou

nt (a

rb u

nit)

O

Cu

CuCu

Cu

CuCu

Si

Si

O

(i)

(ii)

(iii)

1120583m

Figure 3 In the inset of (a) three red squared frames (i) (ii) and (iii) on the high-resolution SEM image of the particle depict the EDXmeasurement positions EDX spectra measured from the positions (i) (ii) and (iii) are shown in (a) (b) and (c) respectively The position(ii) corresponds to the surface of the core particle while the positions (i) and (iii) are the surfaces of attached particles

Journal of Nanomaterials 5

Cu K120572

0 2 4 6 8 10Energy (keV)

Cou

nt (a

rb u

nit)

C K120572

O K120572

Si K120572

(a)

SEM2120583m

(b)

2120583m2120583m Cu K120572

(c)

O K1205722120583m

(d)

Si K1205722120583m

(e)

C K1205722120583m

(f)

Figure 4 (a) EDX spectrum of the observed cross-sectional area shown in secondary-electron topographical TEM image of (b) (c)ndash(f)Elemental mappings of Cu O Si and C respectively

EDX Figure 4(a) shows the EDX spectrum of the cross-sectional area of a cluster generated by X-ray irradiation inthe liquid solution shown in Figure 4(b) which is the STEMimageThe spectra includes necessary elemental informationalong with nonessential signals derived from the TEM gridmount materials (C Al Si andMo) and a Ga signal from thefocused ion beam (FIB) milling process In this manuscriptexcept the carbon C elementary maps of Al Mo and Gaare not shown to avoid cumbersome maps of which providenonessential phenomena Figures 4(c)ndash4(f) show the elemen-tarymaps of CuO Si andC respectively the bright and darkcontrasts correspond to high and low elemental abundancerespectively Note that the elements Si and C remained fromthe polishing agent slurry and mold resin respectively afterFIB milling Thus both elements reside around the particlesnear the TEM grid frame as shown in Figures 4(e) and 4(f)This cross-sectional TEM elementary mapping indicates thatall synthesized particles are at least including Cu as shown inFigure 4(c) and the element C does not play an important rolein the ripping process of the particles By comparison withFigures 4(c) and 4(d) the amount of oxygen (O) is higherincluded in the core particle while oxygen distribution isbarely visible in the small particles attached on the coreparticle (Figure 4(d)) One can see the single crystalline-likestructure in all synthesized particles because we recognized

the several facets in morphology observation using TEM andSEM

To understand the details of the elementary distributionsin the synthesized particles the magnified STEM imagesand EDX mappings are shown in Figure 5 Figure 5(a)shows the topographical STEM image of the cross sectionof the aggregate Figures 5(b) and 5(c) show the EDXelementary mappings of Cu (red-colored) and O (orange-colored) respectively The elemental mappings clearly showanisotropic distributions of Cu and O O is almost detectedin the original single crystalline core region whereas Cu ismainly found in all particles similarly to the results shown inFigures 4 and 5

Furthermore we collected the micro-Raman spectra inorder to reveal crystallographic informationThe photographinsets of Figure 6 show the respective aggregates consistingsome particles The labels (A) (C) and (D) correspond tothe measurement positions of micro-Raman spectroscopiesThe bright green positions correspond to the areas irradiatedby the excitation laser Figures 6(a)ndash6(d) show the micro-Raman spectra of (a) surface of metallic particle (b) siliconsubstrate (c) surface of core particle and (d) particle on thecore particle respectively The micro-Raman spectrometer isso sensitive that it can pick up the information at focal depthof about 500 nmAs shown in Figures 6(a) and 6(d) the broad

6 Journal of Nanomaterials

250nm SEM(a)

250nm Cu K120572(b)

250nm O K120572(c)

Figure 5 (a) High-resolution TEM topographical image of the aggregate cross section ((b) and (c)) Elementary mappings of Cu and Orespectively

spectra are observed indicating that the particles attachingon core particle aremetal and are deduced that the nucleationgrowth or aggregate of Cu particles occurred

Next we focus on the spectrum of Figure 6(c) The peaksat 277 324 520 and 613 cmminus1 appeared clearly in Figure 6(c)These peaks are possibly attributed to summation of threecupric oxides Cu

2O CuO and Cu

4O3[38 39] Although a

comparison of Raman spectra shown in Figures 6(a) 6(c)and 6(d) with that of the Si substrate in Figure 6(b) indicatesthat the peak at 520 cmminus1 is attributed to the Si substratethere remains the undeniable possibility that the peak at520 cmminus1 is derived from A

1g mode of Cu4O3because the

particle volume is thick enough to shade the excitation laserreaching Si substrate Accordingly to the previous studiesof Debbichi et al [39] and Volanti et al [38] our observedRaman signals at 277 324 and 613 cmminus1 from the core particlecorrespond to Raman signals from Ag (2838 cmminus1) and Bg(3335 and 6225 cmminus1) modes of CuO respectively [38 39]In this study the corresponding Raman shifts are a little bitlower than those reported in [40 41] As shown in the insetphotograph of Figure 6(d) after the measurement of Ramanspectra the particles that the laser had been focused on wereslightly melted It is attributed that a red shift was inducedby the heating effect from laser excitation In addition weunderstand the potential of the broad Raman peak structureranging from 500 to 630 cmminus1 being originated from Cu

2O

[38 39] The result may be explainable for CuO (at ) ratiosof the aggregates by comparing with EDX measurementshowever in the present stage it allows us to deduce that thesynthesized particle is expected to be a composited cupricoxide consisting of CuO Cu

2O and Cu

4O3 while some

particles attached to the core particle were deduced to beCu particles Thus in either case we demonstrated one-stepsynthesis of Cucupric oxide and the aggregates induced fromthe liquid solution by direct X-ray irradiation

Various investigations were performed to understandthe mechanism of particle formation based on the inter-action of sonochemical preparation [6ndash13] laser light [18ndash23] microwave irradiation [14ndash17 38 39 41ndash51] and X-ray

and 120574-ray irradiation (radiolysis) [29ndash36 55 56] For pho-tochemical reactions both thermal and electronic excitationeffects were considered and discussed To our knowledge noreport has discussed the particle formation mechanism fromCuSO

4solution under X-ray irradiation Therefore we have

attempted to understand the phenomenological chemicalreaction process

In our experiment hydrated electrons hydroxyl radicalsand hydrogen atomswere the reactive intermediates in the X-ray irradiation of themixed aqueous solution As described inprevious studies the X-ray irradiation from SR provides theproton radical and hydroxyl radical as the following [59ndash65]

H2O

X-ray997888997888997888997888rarr eminusaq

∙H ∙OHH2O2H2 (1)

As described above in this study the X-ray irradiation ofonly CuSO

4solution (without ethanol) did not result in

the formation of any particles This is because the protonand hydroxyl radicals provided by X-ray irradiation are notsufficient to form copper particles via reduction due to thehydration

Upon the addition of an alcohol (eg methanol andethanol) the ∙OH and ∙H radicals are scavenged to yieldreducing organic radicals In the case where ethanol is addedto the solution proton and hydroxyl radicals react as follows[59ndash65]

∙OH (∙H) + CH3CH2OH 997888rarr H2O (H2) + ∙CH

2OH (2a)

CH3CH2OH

X-ray997888997888997888997888rarr CH

3CHO + 2eminus + 2H+ (2b)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr [(CH

3CH2OH)+119899]lowast

+ eminus (2c)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr

(CH3CH2OH)119899minus1

H+ + CH3CHO + eminus

(2d)

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

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International Journal of

Biomaterials

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Advances in

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MaterialsJournal of

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Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 5

Cu K120572

0 2 4 6 8 10Energy (keV)

Cou

nt (a

rb u

nit)

C K120572

O K120572

Si K120572

(a)

SEM2120583m

(b)

2120583m2120583m Cu K120572

(c)

O K1205722120583m

(d)

Si K1205722120583m

(e)

C K1205722120583m

(f)

Figure 4 (a) EDX spectrum of the observed cross-sectional area shown in secondary-electron topographical TEM image of (b) (c)ndash(f)Elemental mappings of Cu O Si and C respectively

EDX Figure 4(a) shows the EDX spectrum of the cross-sectional area of a cluster generated by X-ray irradiation inthe liquid solution shown in Figure 4(b) which is the STEMimageThe spectra includes necessary elemental informationalong with nonessential signals derived from the TEM gridmount materials (C Al Si andMo) and a Ga signal from thefocused ion beam (FIB) milling process In this manuscriptexcept the carbon C elementary maps of Al Mo and Gaare not shown to avoid cumbersome maps of which providenonessential phenomena Figures 4(c)ndash4(f) show the elemen-tarymaps of CuO Si andC respectively the bright and darkcontrasts correspond to high and low elemental abundancerespectively Note that the elements Si and C remained fromthe polishing agent slurry and mold resin respectively afterFIB milling Thus both elements reside around the particlesnear the TEM grid frame as shown in Figures 4(e) and 4(f)This cross-sectional TEM elementary mapping indicates thatall synthesized particles are at least including Cu as shown inFigure 4(c) and the element C does not play an important rolein the ripping process of the particles By comparison withFigures 4(c) and 4(d) the amount of oxygen (O) is higherincluded in the core particle while oxygen distribution isbarely visible in the small particles attached on the coreparticle (Figure 4(d)) One can see the single crystalline-likestructure in all synthesized particles because we recognized

the several facets in morphology observation using TEM andSEM

To understand the details of the elementary distributionsin the synthesized particles the magnified STEM imagesand EDX mappings are shown in Figure 5 Figure 5(a)shows the topographical STEM image of the cross sectionof the aggregate Figures 5(b) and 5(c) show the EDXelementary mappings of Cu (red-colored) and O (orange-colored) respectively The elemental mappings clearly showanisotropic distributions of Cu and O O is almost detectedin the original single crystalline core region whereas Cu ismainly found in all particles similarly to the results shown inFigures 4 and 5

Furthermore we collected the micro-Raman spectra inorder to reveal crystallographic informationThe photographinsets of Figure 6 show the respective aggregates consistingsome particles The labels (A) (C) and (D) correspond tothe measurement positions of micro-Raman spectroscopiesThe bright green positions correspond to the areas irradiatedby the excitation laser Figures 6(a)ndash6(d) show the micro-Raman spectra of (a) surface of metallic particle (b) siliconsubstrate (c) surface of core particle and (d) particle on thecore particle respectively The micro-Raman spectrometer isso sensitive that it can pick up the information at focal depthof about 500 nmAs shown in Figures 6(a) and 6(d) the broad

6 Journal of Nanomaterials

250nm SEM(a)

250nm Cu K120572(b)

250nm O K120572(c)

Figure 5 (a) High-resolution TEM topographical image of the aggregate cross section ((b) and (c)) Elementary mappings of Cu and Orespectively

spectra are observed indicating that the particles attachingon core particle aremetal and are deduced that the nucleationgrowth or aggregate of Cu particles occurred

Next we focus on the spectrum of Figure 6(c) The peaksat 277 324 520 and 613 cmminus1 appeared clearly in Figure 6(c)These peaks are possibly attributed to summation of threecupric oxides Cu

2O CuO and Cu

4O3[38 39] Although a

comparison of Raman spectra shown in Figures 6(a) 6(c)and 6(d) with that of the Si substrate in Figure 6(b) indicatesthat the peak at 520 cmminus1 is attributed to the Si substratethere remains the undeniable possibility that the peak at520 cmminus1 is derived from A

1g mode of Cu4O3because the

particle volume is thick enough to shade the excitation laserreaching Si substrate Accordingly to the previous studiesof Debbichi et al [39] and Volanti et al [38] our observedRaman signals at 277 324 and 613 cmminus1 from the core particlecorrespond to Raman signals from Ag (2838 cmminus1) and Bg(3335 and 6225 cmminus1) modes of CuO respectively [38 39]In this study the corresponding Raman shifts are a little bitlower than those reported in [40 41] As shown in the insetphotograph of Figure 6(d) after the measurement of Ramanspectra the particles that the laser had been focused on wereslightly melted It is attributed that a red shift was inducedby the heating effect from laser excitation In addition weunderstand the potential of the broad Raman peak structureranging from 500 to 630 cmminus1 being originated from Cu

2O

[38 39] The result may be explainable for CuO (at ) ratiosof the aggregates by comparing with EDX measurementshowever in the present stage it allows us to deduce that thesynthesized particle is expected to be a composited cupricoxide consisting of CuO Cu

2O and Cu

4O3 while some

particles attached to the core particle were deduced to beCu particles Thus in either case we demonstrated one-stepsynthesis of Cucupric oxide and the aggregates induced fromthe liquid solution by direct X-ray irradiation

Various investigations were performed to understandthe mechanism of particle formation based on the inter-action of sonochemical preparation [6ndash13] laser light [18ndash23] microwave irradiation [14ndash17 38 39 41ndash51] and X-ray

and 120574-ray irradiation (radiolysis) [29ndash36 55 56] For pho-tochemical reactions both thermal and electronic excitationeffects were considered and discussed To our knowledge noreport has discussed the particle formation mechanism fromCuSO

4solution under X-ray irradiation Therefore we have

attempted to understand the phenomenological chemicalreaction process

In our experiment hydrated electrons hydroxyl radicalsand hydrogen atomswere the reactive intermediates in the X-ray irradiation of themixed aqueous solution As described inprevious studies the X-ray irradiation from SR provides theproton radical and hydroxyl radical as the following [59ndash65]

H2O

X-ray997888997888997888997888rarr eminusaq

∙H ∙OHH2O2H2 (1)

As described above in this study the X-ray irradiation ofonly CuSO

4solution (without ethanol) did not result in

the formation of any particles This is because the protonand hydroxyl radicals provided by X-ray irradiation are notsufficient to form copper particles via reduction due to thehydration

Upon the addition of an alcohol (eg methanol andethanol) the ∙OH and ∙H radicals are scavenged to yieldreducing organic radicals In the case where ethanol is addedto the solution proton and hydroxyl radicals react as follows[59ndash65]

∙OH (∙H) + CH3CH2OH 997888rarr H2O (H2) + ∙CH

2OH (2a)

CH3CH2OH

X-ray997888997888997888997888rarr CH

3CHO + 2eminus + 2H+ (2b)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr [(CH

3CH2OH)+119899]lowast

+ eminus (2c)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr

(CH3CH2OH)119899minus1

H+ + CH3CHO + eminus

(2d)

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

6 Journal of Nanomaterials

250nm SEM(a)

250nm Cu K120572(b)

250nm O K120572(c)

Figure 5 (a) High-resolution TEM topographical image of the aggregate cross section ((b) and (c)) Elementary mappings of Cu and Orespectively

spectra are observed indicating that the particles attachingon core particle aremetal and are deduced that the nucleationgrowth or aggregate of Cu particles occurred

Next we focus on the spectrum of Figure 6(c) The peaksat 277 324 520 and 613 cmminus1 appeared clearly in Figure 6(c)These peaks are possibly attributed to summation of threecupric oxides Cu

2O CuO and Cu

4O3[38 39] Although a

comparison of Raman spectra shown in Figures 6(a) 6(c)and 6(d) with that of the Si substrate in Figure 6(b) indicatesthat the peak at 520 cmminus1 is attributed to the Si substratethere remains the undeniable possibility that the peak at520 cmminus1 is derived from A

1g mode of Cu4O3because the

particle volume is thick enough to shade the excitation laserreaching Si substrate Accordingly to the previous studiesof Debbichi et al [39] and Volanti et al [38] our observedRaman signals at 277 324 and 613 cmminus1 from the core particlecorrespond to Raman signals from Ag (2838 cmminus1) and Bg(3335 and 6225 cmminus1) modes of CuO respectively [38 39]In this study the corresponding Raman shifts are a little bitlower than those reported in [40 41] As shown in the insetphotograph of Figure 6(d) after the measurement of Ramanspectra the particles that the laser had been focused on wereslightly melted It is attributed that a red shift was inducedby the heating effect from laser excitation In addition weunderstand the potential of the broad Raman peak structureranging from 500 to 630 cmminus1 being originated from Cu

2O

[38 39] The result may be explainable for CuO (at ) ratiosof the aggregates by comparing with EDX measurementshowever in the present stage it allows us to deduce that thesynthesized particle is expected to be a composited cupricoxide consisting of CuO Cu

2O and Cu

4O3 while some

particles attached to the core particle were deduced to beCu particles Thus in either case we demonstrated one-stepsynthesis of Cucupric oxide and the aggregates induced fromthe liquid solution by direct X-ray irradiation

Various investigations were performed to understandthe mechanism of particle formation based on the inter-action of sonochemical preparation [6ndash13] laser light [18ndash23] microwave irradiation [14ndash17 38 39 41ndash51] and X-ray

and 120574-ray irradiation (radiolysis) [29ndash36 55 56] For pho-tochemical reactions both thermal and electronic excitationeffects were considered and discussed To our knowledge noreport has discussed the particle formation mechanism fromCuSO

4solution under X-ray irradiation Therefore we have

attempted to understand the phenomenological chemicalreaction process

In our experiment hydrated electrons hydroxyl radicalsand hydrogen atomswere the reactive intermediates in the X-ray irradiation of themixed aqueous solution As described inprevious studies the X-ray irradiation from SR provides theproton radical and hydroxyl radical as the following [59ndash65]

H2O

X-ray997888997888997888997888rarr eminusaq

∙H ∙OHH2O2H2 (1)

As described above in this study the X-ray irradiation ofonly CuSO

4solution (without ethanol) did not result in

the formation of any particles This is because the protonand hydroxyl radicals provided by X-ray irradiation are notsufficient to form copper particles via reduction due to thehydration

Upon the addition of an alcohol (eg methanol andethanol) the ∙OH and ∙H radicals are scavenged to yieldreducing organic radicals In the case where ethanol is addedto the solution proton and hydroxyl radicals react as follows[59ndash65]

∙OH (∙H) + CH3CH2OH 997888rarr H2O (H2) + ∙CH

2OH (2a)

CH3CH2OH

X-ray997888997888997888997888rarr CH

3CHO + 2eminus + 2H+ (2b)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr [(CH

3CH2OH)+119899]lowast

+ eminus (2c)

(CH3CH2OH)119899

X-ray997888997888997888997888rarr

(CH3CH2OH)119899minus1

H+ + CH3CHO + eminus

(2d)

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 7

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

(a)

(C)

200 400 600 800 1000 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

(A)

(B)

(b)

200 400 600 800 1000 1200Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

Cu2O

CuO

Cu4O3

(c)

(D)

200 400 600 1000800 1200Raman shift (cmminus1)

3120583m

Ram

an in

tens

ity (a

rb u

nit)

(d)

Figure 6 (a) Micro-Raman spectrum of the particle attached on the core particle The optical image of a typical aggregate is shown in theinset of (b) The green portion of the inset photograph shown in (B) shows the position irradiated by the green laser (wavelength = 532 nm)Micro-Raman spectra of (b) the Si substrate (c) core and particle attached on the core particle and (d) other particles respectively Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

The several candidates of associated reactions are taking placein the mixed solution under the X-ray irradiation as follows[58 63ndash65]

Cu2+ + 2eminus 997888rarr Cu0 (3a)

Cu2+ + 2CH3CHO + 2 (OHminus) 997888rarr

Cu0 + 2CH3COOH +H

2

(3b)

Cu2+ + 2 (OHminus) 997888rarr Cu (OH)2 (3c)

Cu (OH)2 997888rarr CuO +H2O (3d)

Cu (OH)2 + Cu 997888rarr Cu2O +H

2O (3e)

2CuO + Cu2O 997888rarr Cu

4O3 (3f)

Here the CuO Cu2O Cu

4O3 and Cu particles are finally

reduced and deposited onto the silicon substrate and SiNmembrane

Here we can obtain cubic cuboctahedral and octahedralparticles as shown in Figure 2 The nucleation and growthprocess can be basically explained by LaMer model [66]and the aggregation mechanism derived from the Derjaguin

Landau Verwey and Overbeek (DLVO) model [67 68]In addition for the silicon substrate the H-terminated Sisubstrate produced during the X-ray irradiation may play animportant role in particle synthesis as described in [46]

To investigate the functional group dependence of parti-cle synthesis initiated byX-ray radiolysis we addedmethanol2-propanol or ethylene glycol to 10 CuSO

4solution The

concentration of the additives of methanol and 2-propanolwas the same as the case of X-ray irradiation with ethanolThe mixture ratio of the 10 CuSO

4solution and ethylene

glycol was 500120583L to 05 120583L (solution 5) while the ratio ofthe others (methanol ethanol and 2-propanol) was 200120583Lto 10 120583L As a result the synthesis of particles is confirmedThe SEM images and EDX spectra and micro-Raman spectraof morphologies of particles and surface of Si substrateafter X-ray irradiation of CuSO

4solution with methanol 2-

propanol and ethylene glycol are shown in Figures 7ndash9 10ndash12and 13ndash15 respectively We found that the single crystallinelike particles and their aggregates are also formed in thecases of additive methanol 2-propanol and ethylene glycolrespectively In addition the dappling surfaces where thebright and dark contrasts are randomly distributed in Figures10 and 13 on irradiated area appear in the both cases of X-ray

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

8 Journal of Nanomaterials

200120583m

(a)

100120583m

(b)

1120583m

(c)

100nm

(d)

Figure 7 (a) SEM image of a well-patterned CuSO4solution with added methanol (solution 2) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu NPs nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

1 2 3 4 5 6 7 8 9CO

Cu

Cu

CuSi

Energy (keV)

Cou

nt (a

rb u

nit)

1120583m

(a)

1 2 3 4 5 6 7 8 9CO Cu

Cu Cu

Si

Energy (keV)

Cou

nt (a

rb u

nit)

100nm

(b)

Figure 8 EDX spectra of the red squared areas (a) and (b) in the synthesized particles observed in Figures 7(c) and 7(d) respectively

irradiation under the application of 2-propanol and ethyleneglycol According to the EDX analysis (not shown here) thedappled shade area is consisting of Si This result indicatesthat dips are formed in the dappled shade area by etchingprocess of Si due to X-ray radiolysis with 2-propanol andethylene glycol

To confirm the composition of the synthesized cupricparticles with methanol and 2-propanol we analyzed thesynthesized particles or clusters by EDX spectroscopy asshown in Figures 8 and 11 respectively By comparison withthese spectra the EDX spectra indicate that the synthesizedparticles consisted mostly of Cu Next the micro-Raman

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 9

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

4120583m

(a)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(b)

Ram

an in

tens

ity (a

rb u

nit)

300 600 900 1200Raman shift (cmminus1)

Cu2O

CuO

Cu4O3

(c)

SiRa

man

inte

nsity

(arb

uni

t)

300 600 900 1200

Si

Raman shift (cmminus1)

(d)

Figure 9 Micro-Raman spectra of the measurement positions (a) (b) and (c) on the particle aggregate synthesized from CuSO4solution

mixedwith 2-propanol (solution 4) and Si substrateThe inset photographs display the green laser position on themeasurement area Indexeswere taken from the following Raman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

spectra of the aggregate of these particles are shown in Figures9 and 12 Comparing the spectrum in Figure 9(c) with thatin Figure 12 we found the two spectra are almost the sameand are educed to be derived fromCu

4O3The spectra shown

in Figures 9(a) and 9(b) are similar with Figure 6(c) ofthe case of particles synthesized from CuSO

4solution with

additive ethanol (solution 2) These results indicate thatthe composition of the particles is almost the same and isexpected to be consisting of CuO and Cu

2O The particles

attached on the core particles are expected to be Cu particlesNext we analyzed urchin-like NPs synthesized by X-

ray radiolysis with ethylene glycol (solution 5) by EDXspectroscopy Figure 14 indicates that both the outshoot andcore consisted of cupric oxideThe outshoot seems to contain

a higher proportion of carbon C than the core The micro-Raman spectra of these particles synthesized from solutionwith ethylene glycol (solution 5) are shown in Figure 15Unfortunately the particles were burned after the micro-Raman spectroscopy was measured as shown in the inset ofFigure 15 Comparing the spectrum in Figure 15 with theother spectra depicted in Figures 6 9 and 12 we found thatthe obtained spectrum is expected to be derived from thecomposite consisting of CuO and Cu

2O

We investigate the dependence of the deposited particlesize on the kinds of additive alcohol Here to simplify theestimation of particle size we evaluated the maximum lengthof the synthesized particles because their shapes were variousand diversified The probability densities of the particles

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

10 Journal of Nanomaterials

300120583m

(a)

30120583m

(b)

3120583m

(c)

1120583m

(d)

Figure 10 (a) SEM image of a well-patterned CuSO4solution mixed with 2-propanol (solution 4) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

12108642Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

Si

Cu

500nm

Figure 11 EDX spectrum of the red squared area in the synthesizedparticles observed in Figure 10(d)

synthesized from X-ray radiolysis with (a) methanol (b)ethanol (c) 2-propanol and (d) ethylene glycol are plotted ona function of particle length in Figures 16(a)ndash16(d) respec-tively The synthesized particles under the X-ray irradiationtime of 5min with various additives are similar in size Theresult indicates that the irradiation time of 5min is long

300 600 900 1200

Cu2O

CuO

Cu4O3

Raman shift (cmminus1)

Ram

an in

tens

ity (a

rb u

nit)

4120583m

Cu2O

CuO

Cu4O3

4120583m

Figure 12 Micro-Raman spectra of the measurement position onthe synthesized particle aggregateThe inset photograph displays thelaser spot position on the aggregate Indexes were taken from theRaman spectrum patterns Cu

2O CuO and Cu

4O3[38 39]

enough to complete the series of nucleation growth andaggregation of particles which began and proceeded under

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 11

100120583m

(a)

30120583m

(b)

3120583m

1120583m

(c)

300 nm

(d)

Figure 13 (a) SEM image of a well-patterned CuSO4solution mixed with ethylene glycol (solution 5) after X-ray irradiation for 5min (b)

Magnified SEM image of Cu particles nucleated from the mixed solution under X-ray irradiation ((c) and (d)) High-resolution SEM imagesof the synthesized particles

the competition of LaMer process [66] andDLVO interaction[67 68] Figure 17 shows the dependence of the synthesizedparticle length on the kinds of alcohol It seems that theparticle length increases with the order methanol ethanol2-propanol and ethylene glycol The trend of synthesis ofparticles is derived from the radical activity of alcoholbeing consistent with the previous studies [65] On thebasis of the high-resolution SEM TEM and micro-Ramanspectroscopy we confirmed the synthesis of not only Cuparticles but also higher-order aggregates consisting of cupricoxide and copper particles from liquid solution under X-rayirradiation

As cupric oxide and cupper particles are receiving con-siderable interest due to potential uses as anodes lithiumion cells gas sensors and p-type semiconductor materialsthis X-ray irradiation method can provide a novel additivemanufacturing process [69ndash71] for the devices and systemssuch as solar cells and plasmonic sensor in 120583TAS In additionthis study sheds light on developing a three-dimensionalprinting with both metal and resin as a novel LithographieGalvanoformung Abformung (LIGA) process [72]

4 Conclusion

The present work demonstrates that Cucupric oxide par-ticles can be obtained by irradiating a CuSO

4solution

containing alcohol with SR The synthesized cubic cuboc-tahedral and octahedral NPs aggregate to form higher-order nanomicrostructures High-resolution SEM TEMand micro-Raman spectroscopy analyses demonstrated thatthe core particles consisted of Cu

2O CuO and Cu

4O3 while

the particles attached to the core particles were copperThe additive alcohol helps the copper ions to reduce thecopper colloids cupric oxide particles and Cucupric oxideaggregates Two potential issues have arisen (a) the syntheticprocess including the nucleation and formation of particlesfrom the liquid solution by X-ray irradiation withwithoutethanol or other alcohols and (b) the coagulation of theCucupric oxide particles These issues are worthy of furtherinvestigation

The direct X-ray irradiation using an SR source canprovide an alternative route to explore the novel physicalmechanism of liquidsolid interlayer reaction process fromthe liquid phaseThe higher-order nanomicrostructure con-sisting of metallic particles and metal oxides particles offeran opportunity to conveniently and directly induce catalysisand probe surface enhanced Raman scattering Particularlycupric oxide particles have attracted much attention forapplication of gas sensor and solar cell This one-step directdeposition process can be used in new devices such asldquoLab-on-a-chiprdquo and ldquo120583TAS micron-Total-Analysis-Systemrdquoapplications for chemical and environmental analyses In

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

12 Journal of Nanomaterials

12108642

Cou

nt (a

rb u

nit)

C

O

Cu

Si

Cu

12108642Energy (keV)

Energy (keV)

Cou

nt (a

rb u

nit)

CO

Cu

CuSi

(a)

(a)

(b)

(b)

200nm

Figure 14 EDX spectra of the red squared areas (a) and (b) on the synthesized particles observed in Figure 13(d)

300 600 900 1200

Ram

an in

tens

ity (a

rb u

nit)

Raman shift (cmminus1)

10120583m

Cu2O

CuO

Cu4O3

10120583m

Cu2O

CuO

Cu4O3

Figure 15 Micro-Raman spectrum of the particle aggregate synthesized from CuSO4solution mixed with ethylene glycol (solution 5) The

inset photographs display the green laser position on themeasurement area Indexes were taken from the following Raman spectrumpatternsCu2O CuO and Cu

4O3[38 39]

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 13

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(a)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(b)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(c)

04

03

02

01

0

Prob

abili

ty d

ensit

y

86420Length (120583m)

(d)

Figure 16 Probability densities of the particles synthesized CuSO4mixed with (a) methanol (b) ethanol (c) 2-propanol and (d) ethylene

glycol respectively revealing the particle length distributions

addition the development of this technique combined withthe microfluidic chip enables integrating three-dimensionalprinting which can fabricate micro- or nanoscale structureconsisting of metal and resin

Competing Interests

The authors declare that they have no competing interests

Acknowledgments

The authors are grateful to Dr Yamaguchi of HyogoPrefectural Institute for support during SEM and EDXmeasurement They thank Dr Sugimoto of Aichi PrefecturalInstitute for supporting TEM and EDX measurement Theyappreciate Dr Saiki Dr Takizawa of Hyogo PrefecturalInstitute and Dr Ukita of University of Yamanashi for thefruitful discussion They thank Mitutoyo Association for

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

14 Journal of Nanomaterials

5

4

3

2

1

0Met Eth 2-Pro Et-gly

Part

icle

leng

th (120583

m)

Figure 17 Additive alcohol dependence of synthesized particlelength Met Eth 2-Pro and Et-gly correspond to methanol eth-anol 2-propanol and ethylene glycol respectively

Science and Technology This work is partly supported byStrategic Information andCommunications RampDPromotionProgrammeThese experiments were conducted at the BL8S1of Aichi Synchrotron Radiation Center Aichi Science ampTechnology Foundation Aichi Japan

References

[1] U Kreibig and M Vollmer Optical Properties of Metal Clustersvol 25 of Springer Series in Material Science Springer 1995

[2] E C Le Ru and P G Etchegoin Principles of Surface-EnhancedRaman Spectroscopy and Related Plasmonic Effects ElsevierAmsterdam The Netherlands 2009

[3] X LuM Rycenga S E Skrabalak BWiley and Y Xia ldquoChem-ical synthesis of novel plasmonic nanoparticlesrdquoAnnual Reviewof Physical Chemistry vol 60 pp 167ndash192 2009

[4] B L Cushing V L Kolesnichenko and C J OrsquoConnor ldquoRecentadvances in the liquid-phase syntheses of inorganic nanopar-ticlesrdquo Chemical Reviews vol 104 no 9 pp 3893ndash3946 2004

[5] P Serp and K Philippot Eds Nanomaterials in CatalysisWILEY-VCHVerlag GmbHampCo KGaAWeinheim Germany2013

[6] A Gedanken ldquoUsing sonochemistry for the fabrication ofnanomaterialsrdquoUltrasonics Sonochemistry vol 11 no 2 pp 47ndash55 2004

[7] Y Nagata Y Watananabe S-I Fujita T Dohmaru and STaniguchi ldquoFormation of colloidal silver in water by ultrasonicirradiationrdquo Journal of the Chemical Society Chemical Commu-nications no 21 pp 1620ndash1622 1992

[8] S A Yeung R Hobson S Biggs and F Grieser ldquoFormationof gold sols using ultrasoundrdquo Journal of the Chemical SocietyChemical Communications no 4 pp 378ndash379 1993

[9] J Wagner and J M Kohler ldquoContinuous synthesis of goldnanoparticles in a microreactorrdquo Nano Letters vol 5 no 4 pp685ndash691 2005

[10] J Wagner T Kirner G Mayer J Albert and J M KohlerldquoGeneration of metal nanoparticles in a microchannel reactorrdquoChemical Engineering Journal vol 101 no 1ndash3 pp 251ndash2602004

[11] K S Suslick S-B Choe A A Cichowlas and M W GrinstaffldquoSonochemical synthesis of amorphous ironrdquo Nature vol 353no 6343 pp 414ndash416 1991

[12] W Tu and H Liu ldquoRapid synthesis of nanoscale colloidalmetal clusters by microwave irradiationrdquo Journal of MaterialsChemistry vol 10 no 9 pp 2207ndash2211 2000

[13] T Yamamoto Y Wada T Sakata et al ldquoMicrowave-assistedpreparation of silver nanoparticlesrdquo Chemistry Letters vol 33no 2 pp 158ndash159 2004

[14] G Frens ldquoParticle size and sol stability in metal colloidsrdquoColloid amp Polymer Science vol 250 no 7 pp 736ndash741 1972

[15] G Frens ldquoControlled nucleation for the regulation of theparticle size inmonodisperse gold suspensionsrdquoNature PhysicalScience vol 241 pp 20ndash22 1973

[16] A A Athawale P P Katre M Kumar and M B MajumdarldquoSynthesis of CTAB-IPA reduced copper nanoparticlesrdquo Mate-rials Chemistry and Physics vol 91 no 2-3 pp 507ndash512 2005

[17] M Tsuji M Hashimoto Y Nishizawa M Kubokawa and TTsuji ldquoMicrowave-assisted synthesis of metallic nanostructuresin solutionrdquo ChemistrymdashA European Journal vol 11 no 2 pp440ndash452 2005

[18] A Takami H Kurita and S Koda ldquoLaser-induced size reduc-tion of noble metal particlesrdquoThe Journal of Physical ChemistryB vol 103 no 8 pp 1226ndash1232 1999

[19] S Hashimoto T Uwada M Hagiri and R Shiraishi ldquoMecha-nistic aspect of surface modification on glass substrates assistedby single shot pulsed laser-induced fragmentation of gold nano-particlesrdquo Journal of Physical Chemistry C vol 115 no 12 pp4986ndash4993 2011

[20] F Mafune J-Y Kohno Y Takeda and T Kondow ldquoFormationof stable platinum nanoparticles by laser ablation in waterrdquoJournal of Physical Chemistry B vol 107 no 18 pp 4218ndash42232003

[21] C H Bae S H Nam and SM Park ldquoFormation of silver nano-particles by laser ablation of a silver target in NaCl solutionrdquoApplied Surface Science vol 197-198 pp 628ndash634 2002

[22] K Akamatsu S Ikeda H Nawafune and H YanagimotoldquoDirect patterning of copper on polyimide using ion exchange-able surface templates generated by site-selective surface modi-ficationrdquo Journal of the American Chemical Society vol 126 no35 pp 10822ndash10823 2004

[23] KAkamatsuM Fujii T Tsuruoka S-INakano TMurashimaand H Nawafune ldquoMechanistic study on microstructuraltuning of metal nanoparticlepolymer composite thin layershydrogenation and decomposition of polyimide matrices cat-alyzed by embedded nickel nanoparticlesrdquo Journal of PhysicalChemistry C vol 116 no 33 pp 17947ndash17954 2012

[24] F Fievet J P Lagier B Blin B Beaudoin and M Figlarz ldquoHo-mogeneous and heterogeneous nucleations in the polyol pro-cess for the preparation of micron and submicron size metalparticlesrdquo Solid State Ionics vol 32-33 part 1 pp 198ndash205 1989

[25] L K Kurihara G M Chow and P E Schoen ldquoNanocrystallinemetallic powders and films produced by the polyol methodrdquoNanostructured Materials vol 5 no 6 pp 607ndash613 1995

[26] B Wiley T Herricks Y Sun and Y Xia ldquoPolyol synthesis ofsilver nanoparticles use of chloride and oxygen to promote theformation of single-crystal truncated cubes and tetrahedronsrdquoNano Letters vol 4 no 9 pp 1733ndash1739 2004

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Journal of Nanomaterials 15

[27] L Kvıtek A Panacek J Soukupova et al ldquoEffect of surfactantsand polymers on stability and antibacterial activity of silvernanoparticles (NPs)rdquo Journal of Physical Chemistry C vol 112no 15 pp 5825ndash5834 2008

[28] R Hara T Fukuoka R Takahashi Y Utsumi and A Yam-aguchi ldquoSurface-enhanced Raman spectroscopy using a coffee-ring-type three-dimensional silver nanostructurerdquo RSC Advan-ces vol 5 no 2 pp 1378ndash1384 2015

[29] Q Ma N Moldovan D C Mancini and R A RosenbergldquoSynchrotron-radiation-induced selective-area deposition ofgold on polyimide from solutionrdquo Applied Physics Letters vol76 no 15 p 2014 2000

[30] P H Borse J M Yi J H Je W L Tsai and Y Hwu ldquopHdependence of synchrotron x-ray induced electroless nickeldepositionrdquo Journal of Applied Physics vol 95 no 3 pp 1166ndash1170 2004

[31] P H Borse J M Yi J H Je et al ldquoFormation of magneticNi nanoparticles in x-ray irradiated electroless solutionrdquo Nan-otechnology vol 15 no 6 pp S389ndashS392 2004

[32] Y-C Yang C-H Wang Y-K Hwu and J-H Je ldquoSynchrotronX-ray synthesis of colloidal gold particles for drug deliveryrdquoMaterials Chemistry and Physics vol 100 no 1 pp 72ndash76 2006

[33] C-L Wang B-J Hsao S-F Lai et al ldquoOne-pot synthesis ofAuPt alloyed nanoparticles by intense x-ray irradiationrdquo Nan-otechnology vol 22 no 6 Article ID 065605 2011

[34] F Karadas G Ertas E Ozkaraoglu and S Suzer ldquoX-ray-induced production of gold nanoparticles on a SiO

2Si system

and in a poly(methyl methacrylate) matrixrdquo Langmuir vol 21no 1 pp 437ndash442 2005

[35] H J Lee J H Je Y Hwu and W Tsai ldquoSynchrotron X-ray induced solution precipitation of nanoparticlesrdquo NuclearInstruments and Methods in Physics Research Section B BeamInteractions with Materials and Atoms vol 199 pp 342ndash3472003

[36] A Yamaguchi T Matsumoto I Okada I Sakurai andY Utsumi ldquoSurface-enhanced Raman scattering active goldnanostructure fabricated by photochemical reaction of syn-chrotron radiationrdquo Materials Chemistry and Physics vol 160pp 205ndash211 2015

[37] S K Ghosh and T Pal ldquoInterparticle coupling effect on thesurface plasmon resonance of gold nanoparticles from theoryto applicationsrdquo Chemical Reviews vol 107 no 11 pp 4797ndash4862 2007

[38] D P Volanti D Keyson L S Cavalcante et al ldquoSynthesisand characterization of CuO flower-nanostructure processingby a domestic hydrothermal microwaverdquo Journal of Alloys andCompounds vol 459 no 1-2 pp 537ndash542 2008

[39] L Debbichi M C Marco De Lucas J F Pierson and P KrugerldquoVibrational properties of CuO andCu

4O3from first-principles

calculations and raman and infrared spectroscopyrdquo Journal ofPhysical Chemistry C vol 116 no 18 pp 10232ndash10237 2012

[40] P Poizot S Laruelle S Grugeon L Dupont and J-M Taras-con ldquoNano-sized transition-metal oxides as negative-electrodematerials for lithium-ion batteriesrdquo Nature vol 407 no 6803pp 496ndash499 2000

[41] J C Park A Y Kim J Y Kim S Park K H Park and H SongldquoZnO-CuO core-branch nanocatalysts for ultrasound-assistedazide-alkyne cycloaddition reactionsrdquo Chemical Communica-tions vol 48 no 68 pp 8484ndash8486 2012

[42] A Henglein ldquoFormation and absorption spectrum of coppernanoparticles from the radiolytic reduction of Cu(CN)rdquo The

Journal of Physical Chemistry B vol 104 no 6 pp 1206ndash12112000

[43] J Long J Dong X Wang et al ldquoPhotochemical synthesis ofsubmicron- and nano-scale Cu

2O particlesrdquo Journal of Colloid

and Interface Science vol 333 no 2 pp 791ndash799 2009[44] M A Dar Q Ahsanulhaq Y S Kim J M SohnW B Kim and

H S Shin ldquoVersatile synthesis of rectangular shaped nanobat-like CuO nanostructures by hydrothermal method structuralproperties and growthmechanismrdquoApplied Surface Science vol255 no 12 pp 6279ndash6284 2009

[45] M-S Yeh Y-S Yang Y-P Lee H-F Lee Y-H Yeh and C-SYeh ldquoFormation and characteristics of Cu colloids from CuOpowder by laser irradiation in 2-propanolrdquo Journal of PhysicalChemistry B vol 103 no 33 pp 6851ndash6857 1999

[46] A RadiD Pradhan Y Sohn andKT Leung ldquoNanoscale shapeand size control of cubic cuboctahedral and octahedral Cu-Cu2Ocore-shell nanoparticles on Si(100) by one-step template-

less capping-agent-free electrodepositionrdquo ACS Nano vol 4no 3 pp 1553ndash1560 2010

[47] M Izaki T Shinagawa K-T Mizuno Y Ida M Inaba andA Tasaka ldquoElectrochemically constructed p-Cu

2On-ZnO het-

erojunction diode for photovoltaic devicerdquo Journal of Physics DApplied Physics vol 40 no 11 p 3326 2007

[48] T H Fleisch and G J Mains ldquoReduction of copper oxides byUV radiation and atomic hydrogen studied by XPSrdquo Applica-tions of Surface Science vol 10 no 1 pp 51ndash62 1982

[49] J Tamaki K Shimanoe Y Yamada Y Yamamoto N Miuraand N Yamazoe ldquoDilute hydrogen sulfide sensing propertiesof CuO-SnO

2thin film prepared by low-pressure evaporation

methodrdquo Sensors and Actuators B Chemical vol 49 no 1-2 pp121ndash125 1998

[50] W Shao G Pattanaik and G Zangari ldquoElectrochemical nucle-ation and growth of copper from acidic sulfate electrolytes onn-Si ( 001 )rdquo Journal of the Electrochemical Society vol 154 no7 pp D339ndashD345 2007

[51] J Zhang J Liu Q Peng X Wang and Y Li ldquoNearly monod-isperse Cu

2O and CuO nanospheres preparation and applica-

tions for sensitive gas sensorsrdquo Chemistry of Materials vol 18no 4 pp 867ndash871 2006

[52] R T Clay and R E Cohen ldquoSynthesis of Cu andCuOnanoclus-ters within microphase-separated diblock copolymersrdquo NewJournal of Chemistry vol 22 no 7 pp 745ndash748 1998

[53] I Lisiecki andM P Pileni ldquoSynthesis of coppermetallic clustersusing reversemicelles asmicroreactorsrdquo Journal of theAmericanChemical Society vol 115 no 10 pp 3887ndash3896 1993

[54] M A Brookshier C C Chusuei andDW Goodman ldquoControlof CuO particle size on SiO

2by spin coatingrdquo Langmuir vol 15

no 6 pp 2043ndash2046 1999[55] H Oyanagi Y Orimoto K Hayakawa et al ldquoNanoclusters

synthesized by synchrotron radiolysis in concert with wetchemistryrdquo Scientific Reports vol 4 article 7199 2014

[56] A Yamaguchi I Okada T Fukuoka I Sakurai and Y UtsumildquoSynthesis of metallic nanoparticles through X-ray radioly-sis using synchrotron radiationrdquo Japanese Journal of AppliedPhysics vol 55 no 5 Article ID 055502 2016

[57] T Ishihara M Higuchi T Takagi M Ito H Nishiguchi andY Takita ldquoPreparation of CuO thin films on porous BaTiO

3by

self-assembled multibilayer film formation and application as aCO2sensorrdquo Journal of Materials Chemistry vol 8 no 9 pp

2037ndash2042 1998

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

16 Journal of Nanomaterials

[58] J Luo L Steier M ndashK Son M Schreier M T Mayer and MGratzel ldquoCu

2O nanowire photocathodes for efficient and dura-

ble solar water splittingrdquo Nano Letters vol 16 no 3 pp 1848ndash1857 2016

[59] J Weiss ldquoRadiochemistry of aqueous solutionsrdquo Nature vol153 pp 748ndash750 1944

[60] JWeiss ldquoBiological action of radiationsrdquoNature vol 157 p 5841946

[61] N Miller ldquoQuantitative studies of radiationminusinduced reactionsin aqueous solution I Oxidation of ferrous sulfate by Xminus and120574minusradiationrdquo The Journal of Chemical Physics vol 18 no 1 p79 1950

[62] AH Samuel and J LMagee ldquoTheory of radiation chemistry IITrack effects in radiolysis of waterrdquo The Journal of ChemicalPhysics vol 21 no 6 pp 1080ndash1087 1953

[63] R H Johnsen N T Barker and M Burgin ldquoStudies on iodineas a scavenger in irradiated hydrocarbons and hydrocarbon-alcohol solutionsrdquoThe Journal of Physical Chemistry vol 73 no10 pp 3204ndash3208 1969

[64] N Getoff ldquoRadiation-induced degradation of water pollu-tantsmdashstate of the artrdquo Radiation Physics and Chemistry vol 47no 4 pp 581ndash593 1996

[65] G V Buxton C L Greenstock W P Helman and A B RossldquoCritical Review of rate constants for reactions of hydratedelectrons hydrogen atoms and hydroxyl radicals (sdotOHsdotOminus inAqueous Solutionrdquo Journal of Physical and Chemical ReferenceData vol 17 no 2 p 513 1998

[66] V K LaMer and R H Dinegar ldquoTheory production andmechanism of formation of monodispersed hydrosolsrdquo Journalof the American Chemical Society vol 72 no 11 pp 4847ndash48541950

[67] R Hogg T W Healy and D W Fuerstenau ldquoMutual coag-ulation of colloidal dispersionsrdquo Transactions of the FaradaySociety vol 62 pp 1638ndash1651 1966

[68] J N Israelacvili Intermolecular and Surface Forces AcademicPress London UK 3rd edition 2011

[69] W E Frazier ldquoMetal additive manufacturing a reviewrdquo Journalof Materials Engineering and Performance vol 23 no 6 pp1917ndash1928 2014

[70] K V Wong and A Hernandez ldquoA review of additive manu-facturingrdquo ISRN Mechanical Engineering vol 2012 Article ID208760 10 pages 2012

[71] L Jonusauskas M Lau P Gruber et al ldquoPlasmon assisted 3Dmicrostructuring of gold nanoparticle-doped polymersrdquo Nan-otechnology vol 27 no 15 2016

[72] V Saile U Wallradbe O Tabata and J G Korvink AdvancedMicro and Nanosystems Volume 7 LIGA and Its ApplicationsWiley-VCH Weinheim Germany 2009

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CeramicsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CompositesJournal of

NanoparticlesJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

International Journal of

Biomaterials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CoatingsJournal of

Advances in

Materials Science and EngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Smart Materials Research

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

MetallurgyJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

BioMed Research International

MaterialsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Nano

materials

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal ofNanomaterials