review article hybrid organic-inorganic materials based on...

Review ArticleHybrid Organic-Inorganic Materials Based on Polyoxometalatesand Ionic Liquids and Their Application in Catalysis

Svetlana Ivanova

Departamento de Quımica Inorganica e Instituto de Ciencia de Materiales de Sevilla Centro Mixto Universidad de Sevilla-CSICAvenida Americo Vespucio 49 41092 Sevilla Spain

Correspondence should be addressed to Svetlana Ivanova svetlanaicmsecsices

Received 2 October 2013 Accepted 7 November 2013 Published 28 January 2014

Academic Editors P Maki-Arvela A Ragauskas and A M Seayad

Copyright copy 2014 Svetlana Ivanova This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

An overview of the recent advances in the field of polyoxometalate ionic liquid hybrids is proposed with a special attention paid totheir application in catalysis more precisely biphasic and heterogeneous catalysis Both components of the hybrids are separatelyoutlined pointing to their useful properties and potential for catalysis followed by the description of the hybrids preparationand synergy between components in a large range of organic transformations And finally a vision on the future developmentsis proposed

1 Polyoxometalates General Aspects

Polyoxometalates (POMs) are a class of anionicmetal-oxygenclusters built by the connection of [MO]

119909polyhedra of

the early transition metals in their highest oxidation states[1 2] Nevertheless the strict rules for nomenclature thepolyoxometalate compounds [3] could be referred to alsoas hetero- or isopolyacids and hetero- or isopolyanions orpolyoxoanionsThe most studied polyoxo structures formersare molybdenum (VI) and tungsten (VI) structures resultingfrom accessibility of empty d-orbitals for metal-oxygen 120587-bonding and favorable combination of ionic radius andcharge Polyoxo structures of the hexavalent Tc Re Ru andOs the pentavalent Cr Mo W Tc and Re and tetravalentTi V Cr Mo and W are also known [4] The formationof the polyoxometalate structures obeys generally on twoprinciples (i) each atom must occupy only one edge shared[MO]x polyhedron in which the metal is displaced towardthe edge as a result of the MndashO 120587-bonding and (ii) thestructures with three and more terminal oxo groups are notobserved (known as Lipscomb restriction) [4 5] Althoughthe first polyoxometalates were reported over almost 200years ago continuously new structures are reported togetherwith unusual properties andor applications Various reviewsresume the main application domains of the polyoxomet-alates for example material science medicine or catalysis

[6ndash9] There are literally thousands of compounds in thepolyoxometalate category which defers on their size shapeand composition Recently Long et al [10] proposed a veryelegant way to classify the POMrsquos compounds in-as-calledldquopolyoxometalate periodic tablerdquo They proposed three broadgroups taking into account essentially the anionic metal-oxygen cluster type

(i) Heteropolyanions clusters including heteroatomssuch as [XM

12O40]119899minus anion where M is generally

Mo or W and X is a tetrahedral template Insidethis group three main families could be attributedAnderson [XM

6O119899minus24] Keggin [XM

12O40]119899minus and

Dawson structure [X2M18O62]119899minus with the main dif-

ference being the way of coordination of the het-eroatom (octahedral for Anderson family and tetra-hedral for the other two) [10] Representative schemesof those three structural families of POMs are pre-sented in Figure 1

(ii) Isopolyanions clusters without heteroatoms in theirmolecular structure

(iii) Molybdenum blue and molybdenum brown reducedPOMs a class of highly reduced POM clusters withpotential photochromic and electrochromic applica-tions Despite the fact that these particular POMs

Hindawi Publishing CorporationISRN Chemical EngineeringVolume 2014 Article ID 963792 13 pageshttpdxdoiorg1011552014963792

2 ISRN Chemical Engineering

(a) (b) (c)

Figure 1 The three main families of polyoxometalates (a) Anderson (XM6O24

119899minus

) (b) Keggin (XM12O40

119899minus

) and (c) Dawson structure(X2M18O62

119899minus

)

050

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

100150200250300

Figure 2 Number of published articles containing both poly-oxometalates and hybrids according to Science Direct survey inSeptember 2013

properties will not be a subject of this paper this isthe place to highlight the attractive and promisingcharacter of these materials for that kind of applica-tions At the first place the photo- or electrochromicproperties of the POMs depend on their compositionfor example on the components of the materialand on the synergy between them Since the chargetransfer plays a key role in both phenomena it is veryimportant to increase the charge (electrons holesand protons) interactions between the componentseither by introduction of heteroatoms or by the cross-breeding of the organic and inorganic ions in hybridmaterials The progress in this field was summarizedin various works [11ndash17]

Going back to the classification stated above it should bepointed that it is based only on the polyoxoanion whichis generally compensated by the presence of different typeof cations inorganic (H+ Na+ Cs+ etc) or organic Theorganic cations compensation mechanism results in a newclass of hybrid organicinorganic molecular structures Thisability to combine inorganic and organic components at

molecular level provides one of the newest directions inthe material science pointing the possibility of developingmultifunctional materials on the base of properties tuningThe hybrid materials are constructed then in order to takeadvantage of both inorganic (strength thermal stability andchemical resistance) and organic parts (lightness flexibilityand versatility) but with properties independent of thechemical nature of each component but dependent on thesynergism between them [17]

The POMs hybrids field experiences a continuous devel-opment in the last years A simple search in the ScienceDirect database using keywords as ldquopolyoxometalatesrdquo andldquohybridsrdquo shows an almost exponential increase in the last tenyears (Figure 2)

The hybrid organic polyoxometalates can be separatedin two types [1 18] type I hybrids referring to compoundsin which a weak nonbonding interaction between both(inorganic and organic) parts exists (eg electrostatic hydro-gen bonds and van der Waals interactions) and type IIwhere a stronger bonding interaction takes place (covalentor ionocovalent) The type II hybrids group includes all theorganic ligands allowing a direct substitution of oxo groupof the POMs such as alkoxides carboxylates organosylilderivatives and organoamides Extensive reviews on theadvances in the field of type II POMs were reported byDolbecq et al [1] and Gouzerh and Proust [2] and will notbe a subject of this paper On the contrary this review willfocus on POMderivatives involving nonbonding interactionssuch as molecular complexes between polyoxometalates andorganic substrates and more precisely ionic liquids derivedcations forming ionic salts and their application in the fieldof biphasic and heterogeneous catalysis

It is well known that the proton compensated (H+ H3O+

H5O+2 etc) polyoxometalate anions have several advantages

as heterogeneous catalysts such as very strong Bronsted

ISRN Chemical Engineering 3

acidity approaching the superacid region and fast reversiblemultielectron redox transformations converting them toefficient oxidants These acid-base and redox properties canbe varied by changing the chemical composition [9] Theacidity of the POMs materials originates from the fact thatthe negative charge of the anion is shared over numerousexternal oxygen atoms (36 in Keggin and 56 inWells-Dawsonstructure) thus producing weaker attraction for protonsthan for example in the case of sulphuric acid It has beendemonstrated that MO

6octahedra with one terminal oxygen

are strongly distorted and its partial negative charge residingon the outermost MndashO double bond is generally lower thanthose on the bridging oxide anions embedded within theclusters The counterion (cation) is then shifted towards theexterior of the anion which results in the formation ofa strongly polarized (due to d120587-p120587 interactions) layer ofoxygen atoms inside the polyanion Such polarized oxygenatoms are weakly basic and weakly attract protons [19] Inaddition the acidity of the POMs is strongly affected by theirstructural composition and geometry in a way that closerthe geometry to the spherical one stronger the intrinsic acidcharacter [20]

Although the H3PW12O40and H

3PMo12O40in the solid

state are reported to be stronger Bronsted type acids thanthe conventional HX HY and H-ZSM

5zeolites the question

with the acidity of the salts seems to bemore complex For themetal salts five mechanisms are proposed for the generationof acidity based on (i) the dissociation of occluded watermolecules (ii) on the Lewis acidity of the proper metal ions(iii) on the protons formed by the reduction of themetal ions(iv) on the existing protons in the partially acidic sites or(v) on the partial hydrolysis during the preparation process[8] While the mechanism of acidity formation in these casesis well elucidated the acidity of the hybrid materials is stillunder investigation but should depend on the acidity ofthe POM building block and on the acidity of the organicconstituent and not at the last place on those produced bythe interaction between them

The POMs materials are also known to possess veryflexible redox behaviors which could be finely tuned onpurpose by changing smoothly their composition as forexample adding a heteroatom or by varying their structure[21] As a matter of fact one of the most important electronicproperties of POMs is that of acting as electron reservoirsThe POMs oxidized forms may only accept electrons onthe contrary their reduced forms may behave as donorsor acceptors of several electrons while maintaining theirstructure [22] In fact the POMs owing to their electron andproton transfer andor storage abilities could be reversiblyreduced by addition of various specific numbers of electrons(heteroatoms) which yield in deeply colored mixed valencespecies (ldquoheteropoly bluesrdquo) [23]

All the applications of the POMs (hybrids or not) sincetheir discovery are mainly based on their peculiarities suchas size mass electron and proton transferstorage abilitieslability of the ldquolattice oxygenrdquo and high acidity [4] Howeverthe unabated interest to this kind of materials in almost twocenturies is based on their versatility centered basically onthe possibility of the fine tuning of their properties and

on the high degree of liberty in the moment to choose thestructure pointing directly to the desired application Stillincognitas exist in the elucidation of the hybrids structure andproperties Literally every day a new combination of poly-oxometalate anion and organic cation could be originatedfor which an application should be founded thus opening alarge spectrumof possibilities and research challenges In thiscontext this paper pretends to give an insight in a small butrapidly developing recent area dedicated to the productionstructure elucidation properties and application of a hybridsbased on polyoxometalates and ionic liquids After a smallintroduction of the ionic liquids a detailed description ofthe current state of art on the preparation and applicationin catalysis more precisely in biphasic and heterogeneouscatalysis will be given

2 Ionic Liquids General Aspects

Ionic liquids (ILs) are generally defined as compounds withmelting points below 100∘C consisting entirely of ions mosttypically organic cation (quaternary ammonium salts orbased on cyclic amines) and an inorganic anion Althoughdeveloped as the organic solvents alternative the ionicliquids differ from the latter by their ionic character andtheir structure and organization Coulombic interactionsare the dominant interactions between the ions howeverintermolecular interactions likeHbonding120587-120587 stacking vander Waals interaction and so forth help the supramolecularorganization of the ILs [24 25] The Coulomb interactionsare responsible for the ion pairs formation and for the higherorder ion clusters but the presence of a cooperative networkof hydrogen bonds between them induces the structuraldirectionality [26 27] This directionality presents one of themost interesting features of the ionic liquids especially usefulin the materials synthesis [28ndash31]

Some of the commonly used families of cations andanions forming the ILs are presented in Scheme 1

Analogically to the polyoxometalates some specific ILsphysicochemical properties could be easily tuned by varia-tions of cation and anion which requires good knowledge ofthe field as more than 106 possible combinations are alreadyknown [32] and it is estimated that 1018 different ILs are the-oretically possible [33] The melting point viscosity densitysolubility polarity and aciditycoordination properties aresome examples of the properties subjected to modification[34] These properties are also greatly influenced by themolecular asymmetry built into at least one of the ions forexample the higher the asymmetry of the cation the lower themelting point [35] However in some cases the tunability ofthe properties could also be a disadvantage for example thechange in the structure might result in more than one alteredproperty The ILs are sometimes referred to as ldquodesignerrdquo-solvents [31 36] and some of their principle advantages canbe summarized as follows

(i) ILs have an extremely low vapor pressure they arepractically not volatile

(ii) ILs can dissolve a large range of various organic andinorganic and polar and nonpolar species


R2

R2

R2

R2R2

R3

R3R3

R1 R1

R1

R1

R1

R4R4

N

N+

N+

N+

N+

Alkylimidazolium Alkylpyridinium Alkylpyrrolidinium

Alkylammonium Alkylphosphonium

Clminus AlCl4minus Al2Cl7

minus PF6minus BF4

minus etc

P+

Scheme 1Most commonly used cations and anions forming the ILs

(iii) ILs can form biphasic systems with classical solventstheir low interface tension permits them to adapt tothe second solvent and facilitates the separation of theproducts

(iv) ILs present a wide temperature window of the liquidstate (from 80 to 350∘C)

(v) ILs can have acidic and superacidic properties(vi) ILs often have large electrochemical windows they

can be used as solvents and electrolytes

However the role of the ILs in the chemical reactions isfar away of being simple it can act either as a solvent as acatalyst or presenting a dual charactermdashsolvent and catalystor cocatalyst solvent and support or solvent and ligand [37]

Although the first catalytic process with an IL as a catalystwas carried out in the mid-90s (Friedel-Crafts acylationof benzene in [ethyl methyl imidazolium][Cl]ndashAlCl

3ionic

liquid) [38] the real ldquoboomrdquo of the use of ILs in catalysis startswith the beginning of the 21 century (Figure 3)

Numerous reviews dedicated to the use of ILs in eitherhomogeneous organometallic or heterogeneous catalysis [3337 39ndash41] are published ILs resulted to be very useful inthe field of homogeneous catalysis They could be used assolvents in the ldquobiphasic catalysisrdquo in which the productsand the catalyst separate one from another by its differentmiscibility in ILs and the reuse of the catalyst is possibleAnother emerging field in the ionic liquid catalysis is theimmobilization concept claiming as principal advantages theminimizations of the required amount of often expensive ILsthe diminution of the transport and mass transfer limitationsbetween the existing phases and of course approachingthe IL materials to the heterogeneous catalysts and theiradvantagesmdashfast separation and long-term use Two typesof materials are possible materials consisting of IL catalystsupported on inert solid or thin homogeneous IL layercovering the catalytic material

To some extent the ILs could be considered as theldquoPOMsrdquo of the organic chemistry Although they could notbe considered fully organic their versatility and possibility forproperties design allow the metaphor relating their excep-tional structural and morphological flexibility to those of

0

500

1000

1500

2000

2500

3000

3500

4000

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

Figure 3 The number of published articles containing both ldquoionicliquidrdquo and ldquocatalysisrdquo according to Science Direct survey onSeptember 2013

the polyoxometalates Both types of materials separatelypresents a great potential for use in the heterogeneous catal-ysis and so one could expect that their union will potentiateor combine in a beneficial manner their peculiarities in a newand interesting class of materials

3 Ionic Liquid Polyoxometalates Hybrids

In various studies Ranga Rao and coworkers [42ndash44] used 1-butyl 3methyl imidazolium (Bmim) bromide ionic liquid andseveral heteropolyacids (silicotungstic phosphomolybdic orphosphotungstic) to produce molecular salts with the for-mula [Bmim]

3[XM12O40] The single crystal structural anal-

ysis of the phosphomolybdic hybrid suggests a compoundcrystalizing orthorhombic structure in Pca2

1space group

with one formula unit in the asymmetric unit excludingwatermolecules shown in Figure 4

The method of preparation includes a simpleprecipitation of the salts from aqueous solution of theinitial acid and ionic liquid components The hybrids werecharacterized and the interaction between cation and anionconfirmed by UV-vis DRS and solid state NMR When thehybrid is formed normally a blue shift of the electronictransitions and splits of the CndashH stretching modes ofthe imidazolium ring are observed Ionothermal methodof preparation was proposed by Chen et al [45] for thesynthesis of transition metal containing polyoxotungstateionic liquid hybrids The three synthesized hybrids[Dmim]

2Na3[SiW11O39Fe(H2O)]sdotH

2O (Dmim = 13-

dimethylimidazole) [Eemim]9Na8[(SiW

9O34Fe3(1205832-OH)2

(1205833-O)3(WO)

4]sdot05H

2O (Emim = 1-ethyl3-methylimida-

zole) and [Dmim]2[HMim]Na

6[(AsW

9O33)2(MnIII

(H2O)3]sdot 3H2O (Dmim = 13-dimethylimidazole Mim = 1-

Methylimidazole)The first compound presents amonocliniccrystal structure attributed to the space group C2c in whicheach Dmim cation is connected with three polyoxoanionsvia hydrogen bonds (Figure 5(a)) resulting in the formationof 1D square channels [45]

It is impossible not to realize the analogy of this structureorganization with the ionic liquid 3D arrangements proposedby Dupont [25] As already explained above some ionic


C24

C22

C19

C18 C17

C21

C20

C23

Mo4

Mo3

Mo9

Mo6

Mo11

Mo7

Mo1

Mo2

Mo5

Mo8

Mo10

P1

O25

O30

O26

O23

O17

O16

O4

O10

O15

O22

O40

O11

O33

O31

O8

O7

O2

O6

O13

O38

O20 O36

C9

C10

C11

N4

C12

C13

C14

C15

C16

C6

C7

C8

C5

C4

C3

C2

N1

N2

C1

O21

O19

O34

O35

O27

O29

O28

O1

O12

N6

N5

Figure 4 ORTEP representation of the [Bmim]3[XM12O40] molecular salt reprinted from [42]

liquids in solid state form an extended cooperative networkof cations and anions connected through hydrogen bondsFor the alkyl imidazolium ILs the monomeric unit alwaysconsists of one imidazolium cation surrounded by at leastthree anions (same like in the hybrid) and in turn each anionis surrounded by at least three imidazolium cations Twomajor 3D arrangements in the case of imidazolium ILs arethen formed (i) through chains of the imidazolium rings(120587-stacking Figure 5(b) right) with anions accommodated aschains and (ii) by columns consisting of alternating cationsand anions (left) In both cases ldquofreerdquo volumes with highdegree of directionality imitating tunnels are formed Theanalogy found between both materials suggests clearly thatthe structure organization of the hybrids is governed by thatof the ionic liquid The latter is known as ionic self-assembly(ISA) synthetic strategy and makes use of the electrostaticinteractions between the components It was proposed forthe first time for the interactions between surfactants andcharged polyelectrolytes The structure organization resultsfrom the incompatibility of the surfactant alkyl tails andthe ionic assembly For these mismatched parts a phaseseparation on molecular level could occur thus leading tothe structuration of new materialsmdashthe ionic self-assemblies[46] The properties of the resulted hybrids could be tunedthen trough the variation of the binding factors namelythe concentration of ionic liquid its nature ILs (size andhydrophobicity) the nature of the counterions and so forthRecently Hill [47] underlined the future necessities of thenanostructured functional POM-based materials for theirapplication in catalysis Good knowledge and especially

the control on several points are needed such as (i) the roleand the nature of the counterion (the surfactant or the IL) (ii)the presence of multiple reactive forms rearrangement andisomerization and (iii) the insight of the electronic propertiesof the POMs The principal reaction and hybrids appliedin biphasic or heterogeneous catalysis are summarized inTable 1

The catalytic properties of the hybrids are usuallyconditioned by its composition and method of preparationThe use of microemulsion was reported as a very usefulmethod of preparation of the hybrids based on surfactantsand POMs The claiming advantage of this method is theproduction of a relatively monodispersed nanomaterial[48] The ability to form the emulsion in the case of thehybrids could be used not only for their preparation butalso as a good method of product separation in the biphasiccatalytic systems The microemulsion is achieved whena proper balance of attractive and repulsive interactionson the hydrophobic and hydrophilic side of the interfaceis attained The water oil biphasic emulsion system witha surfactant type of catalyst designed and synthesized byusing a suitable combination of hydrophilic POMs andlipophilic quaternary ammonium cations are reportedby Li et al [49ndash51] for the oxidative desulfurization ofdiesel using H

2O2as oxidant All the studied catalysts

were based on phosphotungstic POM and a surfactantmolecule such as [(C

18H37)2N+(CH

3)2]3[PW12O40]

and [(C18H37)N(CH

3)3]4[H2NaPW

10O40] allowing the

autoassembly of the catalysts directly in the emulsiondroplets It was found that the oxidation activity of


c

b a

4877

989

5

(a)

Me

Me

MeMe

Me

MeNNNN

PF6minus SbF6

minus

++

(b)

Figure 5 (a)The 3D packing structure of [Dmim]2Na3[SiW11O39Fe(H2O)]sdotH

2Oviewed along the [1 1 0] reprinted from [45] (b) Illustration

of the two major 3-D arrangements of imidazolium ILs reprinted from [25]

the catalysts depends on the proper quaternary ammoniumcation and its ability to form metastable emulsions in dieselwith the H

2O2 The higher the ability to form a metastable

emulsion higher the oxidation activity and the better theseparation after reaction either by demulsification or bydecantation Zhu et al [52 53] also report the preparationand application of various metal-based surfactant type ionicliquids peroxomolybdates and peroxotungstates for theoxidative desulfurization of fuel in oilwater mixture Therole of the quaternary ammonium cation was suggested tobe the transfer of the catalytically active compounds to thesulfur containing aromatics thus enhancing the oxidationrate Successful reusability up to 10 cycles for the hybridswas observed Although very good results were obtainedin the catalytic oxidation by POMs of the sulfur containingcompounds in diesel or fuel the use of biphasic systemimplies a mass transfer across the interface of aqueousand oil phases which could be improved by the use of thehybrids but the last separation step is still challenging in alarge-scale application The use of a solid hybrid could bethen envisaged as the next logical step Very recently Zhanget al [54] proposed the use of the [Bmim]

3[PMo

12O40] for

the oxidation of benzothiophenes (BT) dibenzothiophenes(DBT) and 4ndash6 dimethyldibenzothiophene (46-DMDBT)Together with the bare hybrid its immobilized homologues(supported on SiO

2Al2O3or TiO

2) were prepared for

comparison purposes The supported hybrids present higheroxidation activities than the bulk catalysts Diminutionof the rate of the undesired parallel reaction of thermaldecomposition of H

2O2in presence of nitrogen containing

compound (carbazole and quinolone) was also foundThe activity decreases in the order DBT gt 46-DMDBTgt BT The same trend was reported by Li et al [55]for the same reaction using different POM-IL hybrid[Hmim]

5[PMo

10V2O40]mdashcatalytic system very effective

under mild conditions and recyclable up to 6 times withoutsignificant decrease in activity The Keggin based POM-ILhybrid materials [MIMPS]

3PW12O40sdot2H2O (1-(3-sulfonic

group) propyl-3-methyl imidazolium phosphotungstate)[Bmim]

3PW12O40

(1-butyl 3-methyl imidazolium

phosphotungstate) [Bmim]3PMo12O40

(1-butyl 3-methylimidazolium phosphomolybdate) and [Bmim]

4SiW12O40

(1-butyl-3-methyl imidazolium silicotungstate) were appliedby Zhu et al [56] in the oxidative desulfurization of fuelsusing H

2O2as oxidant and ionic liquid as solvent The best

found catalyst was [MIMPS]3PW12O40sdot2H2O with 100

S-removal at 30∘C within one hour Moreover the reactionsystem also exhibited high activity in real diesel oil in whichthe S content was reduced from 1113 ppm to 198 ppm In2013 Chen et al [57] using the activity of those kinds ofhybrids in the desulfurization reaction developed a veryelegant catalytic systemmdashphosphotungstic acid containingionic liquid immobilized on magnetic mesoporous silicaThe magnetic component was added in order to supply anadditional advantage of the system-facile separation of thecatalyst by applying an external magnetic fieldThe oxidationof dibenzothiophene in mild conditions leads to almost100 conversion to DBTO and DBTO

2in very short time

(2ndash8 h) and high degree of recyclability (up to 5) This studyshowed that with an appropriate knowledge of the systemespecially its inconvenientce one could innovate betting onnew systems with additionally improved properties

The ionic liquids are often used for immobilization ofPOMs on silica surface thus producing hybrids directly onthe support surface The active species may be linked by twomain strategies on its support either by ionic interactions(ionic bonds van derWaals) or by covalent bondsThe choiceof the support depends generally on the desired reaction andcould be organic as resin or inorganic as silica Yamaguchiet al [58] reported a few years ago the immobilization ofthe peroxotungstate catalyst on dihydroimidazolium-basedionic liquidmodified SiO

2The immobilized catalyst presents

the same activity in the liquid phase epoxidation of variousolefins by H

2O2as its homogeneous analogue This system

diminishes also the problems with the tungsten leaching andallows the separation and reutilization Tan et al [59] usedalmost the same strategy to immobilize the H

3PW12O40

on1-(3-aminopropyl)-3-propylimidazolium bromine modifiedSBA 15 They use the ability of the SBA-15 supported ionicliquid to carry out the anionic exchange in order to load the


Table1Summaryof

thep

rincipalreactionandhybridsa

ppliedin

biph

asicandheterogeneou

scatalysis

Reactio

nMod

elcompo

und

Hybrid

References

Oxidativ

edesulfuriz

ation

Benzothiop

hene

(BT)

5-methylbenzothioph

enes

(5-M

BT)

dibenzothiop

henes(DBT

)Quaternaryam

mon

ium

POMsc

omplexes

[(C 1

8H37) 2N

+ (CH

3)2]

3[PW

12O

40]a

nd[(C 1

8H37)N

(CH

3)3]

4[H

2NaP

W10O

40]

[49ndash

51]

4-6dimethyldibenzothioph

ene

(46-D

MDBT

)+H

2O2andrealdiesel

DBT

+H

2O2

Surfa

ctanttypeP

OMs[(n-C

8H17) 3N(C

H3)

3]3PO

4[XO

(O) 2] 24

[(n-C 1

2H25) 3NCH

3]3PO

4[XO

(O) 2] 24X=MoandW

[5253]

BTD

BT46-D

MDBT

+H

2O2

[Bmim

] 3[PMo 1

2O40](1-b

utyl3-methylimidazolium

phosph

omolybdate)

[54]

BTD

BTand46-DMDBT

+H

2O2

[Hmim

] 5[PMo 1

0V2O

40]

[55]

Realdieseloil

[MIM

PS] 3PW

12O

40sdot2H

2O(1-(3-sulfonicg

roup

)propyl-3

-methylimidazolium

phosph

otun

gstate)[Bmim

] 3PW

12O

40(1-bu

tyl3-m

ethylimidazolium

phosph

otun

gstate)[Bmim

] 3PM

o 12O

40[Bmim

] 4SiW

12O

40

[56]

DBT

O+H

2O2

Phosph

otun

gstic

acid

containing

ionicliquidim

mob

ilizedon

magnetic

mesop

orou

ssilica

[57]

Epoxidation

Olefi

ns+H

2O2

Peroxotung

stated

ihydroim

idazolium-based

hybrid

onmod

ified

SiO

2[58]

Methyl-9

10octadecenoate+H

2O2+O

2

Peroxotung

stateimmob

ilizedon

amph

iphilic

resin

usingthem

ethylim

idazolea

ndim

idazoleb

ased

ionicliquids

with

different

alkylsub

stitu

tes(fro

mC 6

toC 1

2)as

alin

kers

[63]

Cyclo

octene

+H

2O2

[[n-C 1

6H33N(C

H3)

3]4N

a 3PW

11O

39]

Venturellorsquosanioncoup

ledwith

alkylim

idazolium

catio

nsheterop

olytun

gstate-io

nic

liquidm

odified

silicam

agnetitep

articles

[72]

[77]

[78]

Oleicacid

+H

2O2

Q3PO

4[WO(O

2)2]

4(Q

=qu

aternary

ammon

ium)

[76]

Alco

holsoxidation

benzylalcoho

l+H

2O2

H3PW

12O

40on

1-(3-am

inop

ropyl)-3-prop

ylim

idazolium

brom

inem

odified

SBA15

[59]

Varie

tyof

benzylicalcoho

ls+H

2O2

Phosph

otun

gstic

basedionicliquidcomplex

immob

ilizedon

mesop

orou

ssilica

[61]

Varie

tyof

benzylicandaliphatic

second

aryalcoho

ls1-m

ethyl-3

-butylim

idazolium

decatung

state[bm

im][W

10O

23]

[64]

Benzeneo

xidatio

n+O

2+ascorbicacid

[(C 4

H9)

4N] m[XW

11YO

39H

2O]w

here

X=P5

+ Si

4+G

e4+ B3

+andY=Ti

4+V

5+C

r3+

Mn2

+ Fe

3+C

o2+ Ni2+

Cu2

+ Zn

2+[65]

Methano

l+O

2Bm

im3PMo 1

2O40andBm

im3PW

12O

40[9192]

Hydroxylatio

nBe

nzene+

H2O

2Dicationic(dimethyld

iimidazolium)P

Mo 1

0V2O

405minus

[6667]

Esterifi

catio

nPalm

itica

cidto

biod

iesel

Keggin

tung

stoph

osph

atec

omplex

SO3H

functio

nalized

zwitterion

[68]

Varie

tyof

mon

ocarbo

xylic

acidsw

ithmon

ohydric

alcoho

lsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40andalkyl

ammon

ium

[TEA

PS] 3PW

12O

40[6970]

Transeste

rificatio

nTrim

ethylolpropane

+vario

usfatty

acid

methyleste

rsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40and

alkyl

ammon

ium

[TEA

PS] 3PW

12O

40[71]


PW12O3minus40

anion on the surface as well as partly protonatedamino groups as accelerators to the catalytic process Theamino modified catalysts resulted to be much more activethan the unpromoted ones with 92 of benzyl alcohol con-version with 91 selectivity to benzaldehyde in the selectiveoxidation of benzyl alcohol with H

2O2 The same approach

was used by Cuan and Yan [60] to achieve the multicompo-nent assembly of novel kinds of photofunctional hybrids withpolyoxometalates (Na

9EuW10O36sdot32H2O) and benzoate (4-

aminobenzoate 4-hydroxybenzoate 4-mercaptobenzoate)modified silica through imidazolium ionic liquid (1-methyl-3-trimethoxysilylpropyl) compound as double functionallinkage This study combines more than two functionalitiesto the search of luminescent mesoporous material The newmaterial presents especially strong characteristic Eu3+ lumi-nescence with long decay time and large radiative transitionareas to contribute high quantum efficiency

Instead of employing the anion exchange to charge thePOMs on the IL modified silica surface Zhao et al [61]newly proposed the preparation of the immobilized hybridby one pot synthesis encapsulating directly the hybrid duringthe SBA-15 formation The resulting material showed a goodcatalytic efficiency as a function of alcohol type rangingfrom 30 to 98 of conversion with selectivity to aldehydesoscillating between 50 and 99 The reusability up to 5times with negligible loss of activity was also reportedIt was found that the location of imidazolium cation inthe mesoporous silica is one of the key factors impactingthe catalytic performance The catalyst with POM linkedto bridging organic moieties located in the channel wallsbetween Si centers presented superior TOF and selectivityto aldehydes compared to the catalyst with terminal organicmoieties

Another type of stabilization and immobilization oforganic compounds through host-guest interactions wasrecently summarized in an extensive review [62] Concerningthe hybrids Poli et al [63] presented a very complete andinteresting study on the peroxotungstate catalyst immobi-lization on amphiphilic resin by ion exchange using themethylimidazole and imidazole based ionic liquids withdifferent alkyl substitutes (from C

6to C12) as linkers They

found that the imidazolium group resulted to be the mostappropriate quaternary ammonium group for supporting theperoxophosphotungstate anion In addition if both N atomsin the imidazole are substituted the delocalization of the totalcharge which occurs in the ring increases the total positivecharge and stabilizes in greater extent the POM anion Thecatalytic activities of the hybrids in the epoxidation ofmethyl-9-10-octadecenoate with H

2O2under O

2flow were found to

vary with the hydrophiliclipophilic balance (carbon chainnumber spacers and N-substitution of imidazolium ring)The hybrids resulted in 50 conversion of the fatty acidwith 60 of selectivity to epoxide and a good stability andrecyclability in 2 cycles

Immobilized or bulk the POM-IL hybrids are appliedsuccessfully in a number of organic transformations espe-cially when a good separation and reuse of the catalystare needed For example Chhikara et al [64] developeda simple and efficient protocol for the oxidation in mild

conditions of a variety of benzylic and aliphatic secondaryalcohols by hydrogen peroxide catalyzed by 1-methyl-3-butylimidazolium decatungstate [bmim][W

10O23] in ionic

liquid [bmim][BF4] An easy recovery of the catalytic system

excellent yield of the products (89 to 97 of the desiredketones or aldehydes) and recycling of the catalytic systemwithout much decreasing the yield of the product were alsoreported The benzene oxidation by molecular oxygen tophenol with ascorbic acid as a reducing agent was reportedto be effectively catalyzed by the transition metal exchangedphosphotungstate stabilized with quaternary ammonium salt[(C4H9)4N]m[XW11YO39H2O] where X = P5+ Si4+ Ge4+

B3+ and Y = Ti4+ V5+ Cr3+ Mn2+ Fe3+ Co2+ Ni2+Cu2+ Zn2+ [65] The activity of the POM was positivelyinfluenced by the presence of the transition metal being itsnature the most important factor The presence of ascorbicacid was judged indispensable for the benzene oxidation bymolecular oxygen which partial pressure increase enhancesthe conversion but not the selectivity to phenol The phenolcould be obtained from benzene as well by the hydroxylationof the latter with H

2O2 Some recent studies of Leng et al

[66 67] were devoted to this reaction in which they proposedthe application of a dicationic (dimethyl diimidazolium) anda polymeric ionic liquid to the PMo

10V2O5minus40anion in order to

improve the resistance of the hybrid in excess of H2O2 The

satisfactory results in the case of the dicationic ionic liquidlead to the application of the polymeric one for which highefficient heterogeneous performance was observed (100selectivity with 23 phenol yield) and attributed to thepromotion of the redox properties of the POM by theintramolecular charge transfer from the 120587-electron enrichedcross-linked polymeric IL framework

Series of hybrids based on TPAs ionic liquid coupled withSO3H functionalized zwitterion and Keggin tungstophos-

phate were applied in the esterification of palmitic acidto biodiesel and the optimum conditions were establishedThe use of optimum parameters gave a maximum of 918yield of biodiesel and easy recycling of the catalyst aftera simple treatment [68] The performance of a series ofpolyoxometalate hybrids based on organic cations con-taining either imidazolium [MIMPS]

3PW12O40 pyridinium

[PyPS]3PW12O40 or alkyl ammonium [TEAPS]

3PW12O40

was used as ldquoreaction-induced self-separation catalystsrdquo forvarious esterification reactions [69 70] The good solubilityin the polycarboxylic acid or polyol immiscibility with esterproduct and high melting points of the heteropolyanion-based IL catalysts result in the switching from homogeneousto heterogeneous conditions with good results and recoveryand reuse of this kind of catalysts The ether yield variesbetween 69 and 95 depending on the reactants witharound 7 cycles of reusability with negligible loss of activityThe same series of catalysts together with their phospho-molybdic analogues were applied in the transesterification oftrimethylolpropane with various fatty acid methyl esters [71]The [PyBS]

3PW12O40

catalyst showed several advantagesover the traditional catalysts such as high catalytic activityeasy separation and high yield of desired product It wasfound that this catalyst acted as homogeneous catalyst atthe reaction temperature and converts to a solid state upon


cooling which allows its full recovery and reuse up to 8 timeswithout any significant change of the catalytic activity Thecombination of a certain zwitterion and sodium phospho-tungstate [n-C

16H33N(CH

3)3]4Na3PW11O39] resulted in an

excellent catalyst for the epoxidation of cyclooctene withH2O2 and high TON was reported even in solvent-less

conditions at low temperatures 0∘C A strong cooperativerole between zwitterion and sodium phosphotungstate saltwas found and in addition the hybrid material showed highstructural stability during the reactionThe simple method ofpreparation and the high catalytic activity were reported asprinciple advantages pointing practical applications [72]

The organics stabilized POMs (the as-called Venturelloanion PO

4[(WO(O

2)2]43minus) were extensively applied in

the reaction of epoxidation of alkenes in the late 80s inbiphasic system in the presence of quaternary ammoniumcation (C

6ndashC18) whose role was to transfer the products

from one phase to another [73ndash75] The same approach waslater used by Kozhevnikov et al [76] in the epoxidationof oleic acid by H

2O2in mild conditions The employed

peroxo phosphotungstate yielded 84 of epoxide at 95of oleic acid conversion without using a chlorocarbon sol-vent It was also suggested that in the reaction conditionsvarious peroxophosphotungstate species coexist which couldincrease the rate of the reaction Recently the Venturelloanion was coupled with alkylimidazolium cation to formself-separation catalyst in the epoxidation of olefins [77]Various olefins were transformed efficiently to epoxides withconversion varying between 86 and 98 in ethyl acetatemedia with high selectivity neighboring 99 and up to 5cycles viability Going to a new level Bagheri et al [78]immobilized heteropolytungstate-ionic liquid hybrids on thesurface of silica coated magnetite particles aiming to easethe separation and recycling of the material by adding thesuperparamagnetic properties of themagnetiteThe resultingmaterial showed an excellent activity (84 conversion with99 of selectivity) in the epoxidation of cyclooctene withadvantages in the separation and thermal stability comparedto IL-POM bare systems

The synthesis of 120573-keto enol ethers was selected by Rafieeand Eavani [79] as the reaction of application of the POM-IL hybrids They study the activities of the hybrids as afunction of the IL cation and found that the activity waslittle influenced by the cation contrary to the solubility ofthe hybrids Depending on the polarity of the cations andof the reaction mixture a ldquoself-separationrdquo or heterogeneouscatalysis was observed Regardless of the separation processthe catalyst could be easily recycled and reused several timeswithout significant loss of activity

Rostami et al [80] synthesized di[16-bis(3-methyli-midazolium-1-yl)hexane] decatungstate dehydrate ([C

6

(MIm)2]2W10O32sdot2H2O) hybrid as a novel heteroge-

neous catalyst in the synthesis of 4-arylidene-2-phenyl-5(4)-oxazolones (azlactones) under ultrasound-assistedsolvent-free conditions The novelty of this work liesin the operational and experimental simplicity (easyhybrid synthesis and easy separation and use) enhancedreaction rates and the existence of options for further

transformations of the resulting 4-arylidene-2-phenyl-5(4)-oxazolones into synthetically interesting biologicallyactive compounds The same group continued in thefield of azlactones by the application of 1-butyl-3-methylimidazolium phosphotungstates and phosphomolybdatesin the synthesis of 4-benzylidene-2-phenyloxazoline-5-ones[81] The corresponding azlactones were obtained with goodto excellent yields and catalyst reusability via Erlenmeyersynthesis by the reaction of different aldehydes with hippuricacid and acetic anhydride

Another reaction in which the POM-IL hybrids werereported as efficient inexpensive and recyclable green cat-alyst is the solvent-free synthesis of 18-dioxodecahydroa-cridines The used hybrid was tetrabutylammonium hex-atungstate which catalyzes the one pot synthesis of 18-dioxodecahydroacridines by the reaction of dimedone witharomatic or aliphatic aldehydes in the presence of a nitrogensource (ammonium acetate or aromatic amines) Whencompared to the classical Hantzsch synthetic procedure theuse of this catalyst and reaction path resulted in diminution ofthe reaction time (7ndash14min) higher yields (gt to 90) facilesetup and minimal environmental impact [82]

Tetraalkylammonium salts of transitionmetal substitutedpolyoxometalates such as [(n-C

7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW

11O39Mn] were reported to effi-

ciently catalyze cyclic carbonate synthesis from carbon diox-ide and epoxide [83] The catalytic activity is significantlyinfluenced by the nature of the transition metal substituentandor countercation (Co2+ asympMn2+ gt Ni2+ gt Fe3+ ≫ Cu2+(n-C7H15)4N+ gt (n-C

4H9)4N+ ≫ K+) Especially valuable

catalysts are Co- or Mn-substituted ones which do requireneither additional organic solvents nor additives POM-IL([Hmim]

3PW12O40) hybrid among others was employed

in the acetalization of carbonyl compounds [84] Duringthe reaction the hybrids and the reaction medium formeda temperature-dependent phase separation system whicheased the product transfer and catalyst separation The highactivity of the hybrids (92ndash97 yields) was maintained up to10 cycles of reaction with a negligible loss of activity

Inside the large spectrum of reactions catalyzed by thePOM-IL hybrids an emerging field is the reaction of alcoholsoxidation The oxidation in mild conditions by H

2O2over

polytungstates stabilizedwith quaternary ammonium cationswas broadly reported [85ndash88] However the use of volatileorganic solvents and in most cases the loss of catalyst werenot avoided A few years ago Chhikara et al [89] proposedto use the imidazolium based phosphotungstate complex inionic liquid for the alcohols oxidation to the correspondingcarbonyl groups This oxidation presented the advantage of ahomogeneous reaction mixture easy recovery of the catalystexcellent yields and low degree of solvent consumption Inthe field of alcohols oxidation the oxidation of methanolattracted recently a renewed interest pointing to the on-sitegeneration of H

2for the fuel cells A selective oxidation can

lead to valuable oxygenated products such as formaldehydemethyl formate dimethyl ether and dimethoxymethane andin addition can be used as a model reaction to characterizeacid-base and redox properties of the materials [90]


0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40

Figure 6 Dimethyl ether yield over POM-IL hybrids in gas phasedehydration of methanol from [92]

Pure heterogeneous gas phase dehydrationoxidation ofmethanol over 1-butyl 3-methyl imidazolium based POMhybrids (Bmim

3PMo12O40

and Bmim3PW12O40) was

reported by Ivanova et al [91 92] The fresh hybrids donot catalyze the dehydration of methanol but after someactivation procedure showed a high activity in the harshrange of selected reaction conditions (activation at 400∘Cin methanolair mixture and 275∘C for the dehydration)in comparison to the analogues metal salt Cs

2HPW

12O40

(Figure 6)Special attention in these works was paid to the stability

and corresponding activity of the hybrids as a function ofthe temperature In the activation conditions a full oxida-tion of methanol was obtained and at the temperature ofdehydration dimethyl ether was produced with selectivityexceeding 95 A close relationship between the nature ofthe POM anion and the thermal stability range was observedThe Mo based POM seems to catalyze the oxidation ofthe imidazolium cation and the destruction of the hybridduring the activation contrary to the W-based POM whichactive site seems to be the imidazolium deficient hybridThe differences between the acidic and redox properties ofboth hybrids are responsible for their different behaviorBoth types of properties can be controlled either by thePOM part or by the IL modification Those studies open thedoor to the direct application of the POM-IL materials inthe gas phase heterogeneous catalysis In this area a lot ofwork has to be done Recently Dermeche et al [93] foundthat the product distribution of the selective oxidation ofmethanol depends on the polyanion composition and on theframework symmetry The different heteroatom introducedin the Dawson structure based polyoxometalates allows thecontrol of the dehydration oxidation products

Where Is the Future

The increasing development of hybrid systems in the lastdecade indicates by itself that they are a class of forthcoming

and promising materials The extensive use of the polyox-ometalates in the acid catalysis and especially their ability toactivateH

2O2[94] opened the possibility for their application

in the acid and oxidation catalysis in mild conditions Thediversity of the polyoxometalate structures and the goodknowledge of their structureproperties relationship providethe necessary foundation in the field but their synergismwiththe ionic liquids still remains underexplored The majorityof the reports in the literature deal with the imidazoliumor quaternary ammonium based family organic cations andthe inorganic part is mainly based on Keggin structuresThe diversity in both inorganic and organic families couldresult in an extensive development of the application targetedhybrids Their special photochromic and electrochromicbehavior should not be forgotten opening a large field ofpossible application in the materials science The applicationof these hybrids in the gas phase medium temperaturereactions still has not revealed its truly potential but the firststep is made good productivity in the methanol dehydrationreaction was found

The field of biofuels production and natural productsvalorization is one of the newest fields in catalysis aiming atthe replacement of the limited fossil fuels and the decreasingof the environmental impact Among the current renewableand sustainable alternatives the 5-hydroxymethylfurfural(HMF) converted from sugars is a versatile and key inter-mediate in biofuel and petroleum chemistry [95 96] Theionic liquids have been already reported for the productionof HMF [97ndash99] and very recently the application of thepolyacids based catalyst with excellent efficiency and verygood selectivity was reported [100] The combination ofboth catalysts seems to be the next logical step targetinghigher stability and more importantly higher productivity byapplying it in heterogeneous in-flow reactions

Regardless of the field of application material sciencecatalysis or medicine the polyoxometalate derivatives wereare and will be always one of the top materials for researchand developing

Conflict of Interests

The author declares that there is no conflict of interestsregarding the publication of this paper

References

[1] A Dolbecq E Dumas C R Mayer and P Mialane ldquoHybridorganic-inorganic polyoxometalate compounds from struc-tural diversity to applicationsrdquo Chemical Reviews vol 110 no10 pp 6009ndash6048 2010

[2] P Gouzerh and A Proust ldquoMain-group element organic andorganometallic derivatives of polyoxometalatesrdquo ChemicalReviews vol 98 no 1 pp 77ndash111 1998

[3] Y P Jeannin ldquoThe nomenclature of polyoxometalates how toconnect a name and a structurerdquo Chemical Reviews vol 98 no1 pp 51ndash76 1998

[4] M T Pope and A Muller ldquoPolyoxometalate chemistry an oldfield with new dimensions in several disciplinesrdquo AngewandteChemie vol 30 no 1 pp 34ndash48 1991


[5] M T Pope and AMuller Eds Polyoxometalates From PlatonicSolids to Anti-Retroviral Activity Kluwer Academic PublishersDordrecht The Netherlands 1994

[6] D E Katsoulis ldquoA survey of applications of polyoxometalatesrdquoChemical Reviews vol 98 no 1 pp 359ndash387 1998

[7] J T Rhule C L Hill D A Judd and R F Schinazi ldquoPolyox-ometalates in medicinerdquo Chemical Reviews vol 98 no 1 pp327ndash357 1998

[8] NMizuno andMMisono ldquoHeterogeneous catalysisrdquoChemicalReviews vol 98 no 1 pp 199ndash217 1998

[9] I V Kozhevnikov ldquoCatalysis by heteropoly acids andmulticom-ponent polyoxometalates in liquid-phase reactionsrdquo ChemicalReviews vol 98 no 1 pp 171ndash198 1998

[10] D-L Long R Tsunashima and L Cronin ldquoPolyoxometalatesbuilding blocks for functional nanoscale systemsrdquo AngewandteChemie International Edition vol 49 no 10 pp 1736ndash1758 2010

[11] T Yamase ldquoPhoto- and electrochromism of polyoxometalatesand related materialsrdquo Chemical Reviews vol 98 no 1 pp 307ndash325 1998

[12] S Liu and Z Tang ldquoPolyoxometalate-based functional nanos-tructured films current progress and future prospectsrdquo NanoToday vol 5 no 4 pp 267ndash281 2010

[13] A B Bourlinos K Raman R Herrera Q Zhang L A Archerand E P Giannelis ldquoA liquid derivative of 12-tungstophosphoricacid with unusually high conductivityrdquo Journal of the AmericanChemical Society vol 126 no 47 pp 15358ndash15359 2004

[14] B Xu L Xu G Gao W Guo and S Liu ldquoEffects of filmstructure on electrochromic properties of the multilayer filmscontaining polyoxometalatesrdquo Journal of Colloid and InterfaceScience vol 330 no 2 pp 408ndash414 2009

[15] P Gomez-Romero ldquoPolyoxometalates as photoelectrochemicalmodels for quantum-sized colloidal semiconducting oxidesrdquoSolid State Ionics vol 101ndash103 no 1 pp 243ndash248 1997

[16] J A F Gamelas A M V Cavaleiro E De Matos GomesM Belsley and E Herdtweck ldquoSynthesis properties and pho-tochromism of novel charge transfer compounds with Kegginanions and protonated 221015840-biquinolinerdquo Polyhedron vol 21 no25-26 pp 2537ndash2545 2002

[17] T He and J Yao ldquoPhotochromism in composite and hybridmaterials based on transition-metal oxides and polyoxometa-latesrdquo Progress in Materials Science vol 51 no 6 pp 810ndash8792006

[18] Y-F Song D-L Long C Ritchie and L Cronin ldquoNanoscalepolyoxometalate-based inorganicorganic hybridsrdquo ChemicalRecord vol 11 no 3 pp 158ndash171 2011

[19] R Tayebee F Nehzat E Rezaei-Seresht F Z Mohammadiand E Rafiee ldquoAn efficient and green synthetic protocol for thepreparation of bis(indolyl)methanes catalyzed by H6P2W18O62 sdot

24H2O with emphasis on the catalytic proficiency of Wells-Dawson versus Keggin heteropolyacidsrdquo Journal of MolecularCatalysis A vol 351 pp 154ndash164 2011

[20] J P JolivetMetal Oxide Chemistry and Synthesis JohnWilley ampSons Chichester UK 2000

[21] M T Pope ldquoPolyoxo anions synthesis and structurerdquo inComprehensive Coordination Chemistry II Transition MetalGroups A G Wedd Ed vol 4 pp 635ndash678 Elsevier ScienceNew York NY USA 2004

[22] B Keita and L Nadjo ldquoPolyoxometalate-based homogeneouscatalysis of electrode reactions recent achievementsrdquo Journal ofMolecular Catalysis A vol 262 no 1-2 pp 190ndash215 2007

[23] M Clemente-Leon E Coronado A Soriano-Portillo C Min-gotaud and J M Dominguez-Vera ldquoLangmuir-Blodgett filmsbased on inorganic molecular complexes with magnetic oroptical propertiesrdquo Advances in Colloid and Interface Sciencevol 116 no 1-3 pp 193ndash203 2005

[24] J Dupont ldquoOn the solid liquid and solution structural orga-nization of imidazolium ionic liquidsrdquo Journal of the BrazilianChemical Society vol 15 no 3 pp 341ndash350 2004

[25] J Dupont ldquoFrommolten salts to ionic liquids a ldquonanordquo journeyrdquoAccounts of Chemical Research vol 44 no 11 pp 1223ndash12312011

[26] C S Consorti P A Z Suarez R F De Souza et al ldquoIdentifica-tion of 13-dialkylimidazoIium salt supramolecular aggregatesin solutionrdquo Journal of Physical Chemistry B vol 109 no 10 pp4341ndash4349 2005

[27] J Dupont P A Z Suarez R F De Souza R A Bur-row and J-P Kintzinger ldquoC-H-120587 interactions in 1-n-butyl-3-methylimidazolium tetraphenylborate molten salt solid andsolution structuresrdquo Chemistry A European Journal vol 6 no13 pp 2377ndash2381 2000

[28] M Antonietti D Kuang B Smarsly and Y Zhou ldquoIonic liquidsfor the convenient synthesis of functional nanoparticles andother inorganic nanostructuresrdquo Angewandte Chemie Interna-tional Edition vol 43 no 38 pp 4988ndash4992 2004

[29] A Taubert ldquoInorganic materials synthesismdasha bright future forionic liquidsrdquo Acta Chimica Slovenica vol 52 no 3 pp 183ndash186 2005

[30] A Taubert and Z Li ldquoInorganic materials from ionic liquidsrdquoDalton Transactions no 7 pp 723ndash727 2007

[31] J M Martınez Blanes B M Szyja F Romero-Sarria et alldquoMultiple zeolite structures from one ionic liquid templaterdquoChemistry A European Journal vol 19 pp 2122ndash2130 2013

[32] S Werner M Haumann and P Wasserscheid ldquoIonic liquidsin chemical engineeringrdquo in Annual Review of Chemical andBiomolecular Engineering J M Prausnitz M F Doherty andM A Segalman Eds vol 1 pp 203ndash230 2010

[33] Q Zhang S Zhang and Y Deng ldquoRecent advances in ionicliquid catalysisrdquo Green Chemistry vol 13 no 10 pp 2619ndash26372011

[34] S Werner M Haumann and P Wasserscheid ldquoIonic liquidsin chemical engineeringrdquo Annual Review of Chemical andBiomolecular Engineering vol 1 pp 203ndash230 2010

[35] K R Seddon ldquoRoom-temperature ionic liquids neoteric sol-vents for clean catalysisrdquo Kinetics and Catalysis vol 37 no 5pp 693ndash697 1996

[36] M J Earle and K R Seddon ldquoIonic liquids Green solvents forthe futurerdquo Pure and Applied Chemistry vol 72 no 7 pp 1391ndash1398 2000

[37] H Olivier-Bourbigou L Magna and D Morvan ldquoIonic liquidsand catalysis recent progress from knowledge to applicationsrdquoApplied Catalysis A vol 373 no 1-2 pp 1ndash56 2010

[38] J A Boon J A Levisky J L Pflug and J S Wilkes ldquoFriedel-Crafts reactions in ambient-temperature molten saltsrdquo Journalof Organic Chemistry vol 51 no 4 pp 480ndash483 1986

[39] V I Parvulescu and C Hardacre ldquoCatalysis in ionic liquidsrdquoChemical Reviews vol 107 no 6 pp 2615ndash2665 2007

[40] J Dupont R F De Souza and P A Z Suarez ldquoIonic liquid(molten salt) phase organometallic catalysisrdquoChemical Reviewsvol 102 no 10 pp 3667ndash3692 2002

[41] Y Gu and G Li ldquoIonic liquids-based catalysis with solids stateof the artrdquo Advanced Synthesis and Catalysis vol 351 no 6 pp817ndash847 2009


[42] G Ranga Rao T Rajkumar and B Varghese ldquoSynthesis andcharacterization of 1-butyl 3-methyl imidazolium phospho-molybdate molecular saltrdquo Solid State Sciences vol 11 no 1 pp36ndash42 2009

[43] T Rajkumar and G Ranga Rao ldquoSynthesis and characterizationof hybrid molecular material prepared by ionic liquid andsilicotungstic acidrdquoMaterials Chemistry andPhysics vol 112 no3 pp 853ndash857 2008

[44] T Rajkumar and G Ranga Rao ldquoCharacterization of hybridmolecular material prepared by 1-butyl 3-methyl imidazoliumbromide and phosphotungstic acidrdquo Materials Letters vol 62no 25 pp 4134ndash4136 2008

[45] W-L Chen B-W Chen H-Q Tan Y-G Li Y-H Wangand E-B Wang ldquoIonothermal syntheses of three transition-metal-containing polyoxotungstate hybrids exhibiting the pho-tocatalytic and electrocatalytic propertiesrdquo Journal of Solid StateChemistry vol 183 no 2 pp 310ndash321 2010

[46] T Zhang J Brown R J Oakley and C F J Faul ldquoTowardsfunctional nanostructures ionic self-assembly of polyoxomet-alates and surfactantsrdquo Current Opinion in Colloid and InterfaceScience vol 14 no 2 pp 62ndash70 2009

[47] C L Hill ldquoProgress and challenges in polyoxometalate-basedcatalysis and catalytic materials chemistryrdquo Journal ofMolecularCatalysis A vol 262 no 1-2 pp 2ndash6 2007

[48] M Masteri-Farahani and S Shahbazi ldquoPreparation of Keggin-type polyoxometalate hybrid nanomaterial with one pot multi-component reaction in reverse micelle nanoreactorsrdquo InorganicChemistry Communications vol 15 pp 297ndash300 2012

[49] C Li J Gao Z Jiang et al ldquoSelective oxidations on recoverablecatalysts assembled in emulsionsrdquoTopics inCatalysis vol 35 no1-2 pp 169ndash175 2005

[50] C Li Z Jiang J Gao et al ldquoUltra-deep desulfurization of dieseloxidation with a recoverable catalyst assembled in emulsionrdquoChemistry A European Journal vol 10 no 9 pp 2277ndash22802004

[51] H Lu J Gao Z Jiang et al ldquoUltra-deep desulfurization of dieselby selective oxidation with [C

18H37N(CH

3)3]4[H2NaPW

10O36]

catalyst assembled in emulsion dropletsrdquo Journal of Catalysisvol 239 no 2 pp 369ndash375 2006

[52] W Zhu G Zhu H Li et al ldquoOxidative desulfurization of fuelcatalyzed by metal-based surfactant-type ionic liquidsrdquo Journalof Molecular Catalysis A vol 347 no 1-2 pp 8ndash14 2011

[53] W Zhu G Zhu H Li et al ldquoCatalytic kinetics of oxidativedesulfurization with surfactant type polyoxometalates basedionic liquidsrdquo Fuel Processing Technology vol 106 pp 70ndash762013

[54] J Zhang A Wang X Li and X Ma ldquoOxidative desulfurizationof dibenzothiophene and diesel over [Bmim]

3PMo12O40rdquo Jour-

nal of Catalysis vol 279 no 2 pp 269ndash275 2011[55] J Li B Hu and C Hu ldquoDeep desulfurization of fuels by

heteropolyanion-based ionic liquidrdquo Bulletin of the KoreanChemical Society vol 34 pp 225ndash230 2013

[56] W Zhu W Huang H Li et al ldquoPolyoxometalate-based ionicliquids as catalysts for deep desulfurization of fuelsrdquo FuelProcessing Technology vol 92 no 10 pp 1842ndash1848 2011

[57] Y Chen F Zhang Y Fang et al ldquoPhosphotungstic acidcontaining ionic liquids immobilized on magnetic mesoporoussilica rod catalyst for the oxidation of dibenzothiophene withH2O2rdquo Catalysis Communications vol 38 pp 54ndash58 2013

[58] K Yamaguchi C Yoshida S Uchida and N Mizuno ldquoPer-oxotungstate immobilized on ionic liquid-modified silica as

a heterogeneous epoxidation catalyst with hydrogen peroxiderdquoJournal of the AmericanChemical Society vol 127 no 2 pp 530ndash531 2005

[59] R Tan C Liu N Feng et al ldquoPhosphotungstic acid loaded onhydrophilic ionic liquidmodified SBA-15 for selective oxidationof alcohols with aqueous H

2O2rdquo Microporous and Mesoporous

Materials vol 158 pp 77ndash87 2012[60] J Cuan and B Yan ldquoPhotofunctional hybrid materials with

polyoxometalates and benzoate modified mesoporous silicathrough double functional imidazolium ionic liquid linkagerdquoMicroporous and Mesoporous Materials vol 163 pp 9ndash16 2014

[61] H Zhao L Zeng Y Li et al ldquoPolyoxometalate-based ioniccomplexes immobilized in mesoporous silica via a one-potprocedure efficient and reusable catalyst for H

2O2mediated

alcohol oxidations in aqueous mediardquo Microporous and Meso-porous Materials vol 172 pp 67ndash76 2013

[62] R Yu X-F Kuang X-Y Wu C-Z Lu and J P Donahue ldquoSta-bilization and immobilization of polyoxometalates in porouscoordination polymers through host-guest interactionsrdquo Coor-dination Chemistry Reviews vol 253 no 23-24 pp 2872ndash28902009

[63] E Poli J-M Clacens and Y Pouilloux ldquoSynthesis of per-oxophosphotungstate immobilized onto polymeric support asheterogeneous catalyst for the epoxidation of unsaturated fattyestersrdquo Catalysis Today vol 164 no 1 pp 429ndash435 2011

[64] B S Chhikara S Tehlan and A Kumar ldquo1-Methyl-3-butylimidazolium decatungstate in ionic liquid an efficientcatalyst for the oxidation of alcoholsrdquo Synlett vol 2005 no 1pp 63ndash66 2005

[65] Y Liu K Murata and M Inaba ldquoLiquid-phase oxidation ofbenzene to phenol by molecular oxygen over transition metalsubstituted polyoxometalate compoundsrdquo Catalysis Communi-cations vol 6 no 10 pp 679ndash683 2005

[66] Y Leng J Wang D Zhu L Shen P Zhao and M ZhangldquoHeteropolyanion-based ionic hybrid solid a green bulk-typecatalyst for hydroxylation of benzene with hydrogen peroxiderdquoChemical Engineering Journal vol 173 no 2 pp 620ndash626 2011

[67] P Zhao Y Leng and J Wang ldquoHeteropolyanion-pairedcross linked copolymer an efficient heterogeneous catalyst forhydroxylation of benzene with hydrogen peroxiderdquo ChemicalEngineering Journal vol 204ndash206 pp 72ndash78 2012

[68] X-X Han Y-F He C-T Hung S-L Liu S-J Huang andS-B Liu ldquoEfficient and reusable polyoxometalate-based sul-fonated ionic liquid catalysts for palmitic acid esterification tobiodieselrdquo Chemical Engineering Science

[69] Y Leng J Wang D Zhu X Ren H Ge and L ShenldquoHeteropolyanion-based ionic liquids reaction-induced self-separation catalysts for esterificationrdquo Angewandte ChemieInternational Edition vol 48 no 1 pp 168ndash171 2009

[70] Y Leng J Wang D Zhu Y Wu and P Zhao ldquoSulfonatedorganic heteropolyacid salts recyclable green solid catalysts foresterificationsrdquo Journal ofMolecular Catalysis A vol 313 no 1-2pp 1ndash6 2009

[71] K Li L Chen H Wang W Lin and Z Yan ldquoHeteropolyacidsalts as self-separation and recyclable catalysts for transesterifi-cation of trimethylolpropanerdquo Applied Catalysis A vol 392 no1-2 pp 233ndash237 2011

[72] Y Qiao L Hua J Chen N Theyssen W Leitner and Z HouldquoThe cooperative role of zwitterions and phosphotungstateanion in epoxidation reactionrdquo Journal of Molecular CatalysisA vol 380 pp 43ndash48 2013


[73] C Venturello E Alneri andM Ricci ldquoA new effective catalyticsystem for epoxidation of olefins by hydrogen peroxide underphase-transfer conditionsrdquo Journal of Organic Chemistry vol48 no 21 pp 3831ndash3833 1983

[74] C Venturello and R DrsquoAloisio ldquoQuaternary ammoniumtetrakis(diperoxotungsto)phosphates(3-) as a new class of cat-alysts for efficient alkene epoxidation with hydrogen peroxiderdquoJournal of Organic Chemistry vol 53 no 7 pp 1553ndash1557 1988

[75] C Venturello R DrsquoAloisio J C J Bart and M Ricci ldquoANew peroxotungsten heteropoly anion with special oxidiz-ing properties synthesis and structure of tetrahexylammo-nium tetra(diperoxotungsto)phosphate(3-)rdquo Journal of Molecu-lar Catalysis vol 32 no 1 pp 107ndash110 1985

[76] I V Kozhevnikov G P Mulder M C Steverink-de Zoete andM G Oostwal ldquoEpoxidation of oleic acid catalyzed by peroxophosphotungstate in a two-phase systemrdquo Journal of MolecularCatalysis A vol 134 no 1ndash3 pp 223ndash228 1998

[77] H Li Z Hou Y Qiao et al ldquoPeroxopolyoxometalate-basedroom temperature ionic liquid as a self-separation catalyst forepoxidation of olefinsrdquo Catalysis Communications vol 11 no 5pp 470ndash475 2010

[78] M Bagheri M Masteri-Farahani and M Ghorbani ldquoSynthesisand characterization of heteropolytungstate-ionic liquid sup-ported on the surface of silica coated magnetite nanoparticlesrdquoJournal of Magnetism and Magnetic Materials vol 327 pp 58ndash63 2013

[79] E Rafiee and S Eavani ldquoPolyoxometalate-based acid saltswith tunable separation properties as recyclable Bronsted acidcatalysts for the synthesis of 120573-keto enol ethersrdquo CatalysisCommunications vol 25 pp 64ndash68 2012

[80] M Rostami A R Khosropour V Mirkhani I Moham-madpoor-Baltork M Moghadam and S Tangestaninejadldquo[C6(MIm)2]2W10O32 sdot 2H2O a novel and powerful catalyst forthe synthesis of 4-arylidene-2-phenyl-5(4)-oxazolones underultrasonic conditionrdquo Comptes Rendus Chimie vol 14 no 10pp 869ndash877 2011

[81] M Rostami A Khosropour V Mirkhani M Moghadam STangestaninejad and I Mohammadpoor-Baltork ldquoOrganic-inorganic hybrid polyoxometalates efficient heterogeneousand reusable catalysts for solvent-free synthesis of azlactonesrdquoApplied Catalysis A vol 397 no 1-2 pp 27ndash34 2011

[82] A Davoodnia A Zare-Bidaki and H Behmadi ldquoA rapid andgreen method for solvent free synthesis of 18-dioxodecahy-droacridines using tetrabutylammonium hexatungstate asreusable heterogeneous catalystrdquo Chinese Journal of Catalysisvol 33 pp 1797ndash1801 2012

[83] H Yasuda L-NHe T Sakakura andCHu ldquoEfficient synthesisof cyclic carbonate from carbon dioxide catalyzed by polyox-ometalate the remarkable effects of metal substitutionrdquo Journalof Catalysis vol 233 no 1 pp 119ndash122 2005

[84] Y Dai B D Li H D Quan and C X Lu ldquo[Hmim]3PW12O40 a

high-efficient and green catalyst for the acetalization of carbonylcompoundsrdquo Chinese Chemical Letters vol 21 no 6 pp 678ndash681 2010

[85] Y Ishii H Tanaka and Y Nishiyama ldquoSelectivity inoxidation of sulfides with hydrogen peroxide by [n-C

5

H5N+(CH

2)15CH3]3PM12O 3minus40

and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O

2)2]43minus (M = Mo or W)rdquo Chemistry

Letters vol 23 pp 1ndash4 1994[86] N M Gresley W P Griffith A C Laemmel H I S Nogueira

andB C Parkin ldquoStudies on polyoxo and polyperoxo-metalates

part 5 peroxide-catalysed oxidations with heteropolyperoxo-tungstates and -molybdatesrdquo Journal of Molecular Catalysis Avol 117 no 1ndash3 pp 185ndash198 1997

[87] K Sato M Hyodo M Aoki X-Q Zheng and R NoyorildquoOxidation of sulfides to sulfoxides and sulfones with 30hydrogen peroxide under organic solvent- and halogen-freeconditionsrdquo Tetrahedron vol 57 no 13 pp 2469ndash2476 2001

[88] N Mizuno and K Kamata ldquoCatalytic oxidation of hydrocar-bons with hydrogen peroxide by vanadium-based polyoxomet-alatesrdquo Coordination Chemistry Reviews vol 255 no 19-20 pp2358ndash2370 2011

[89] B S Chhikara R Chandra and V Tandon ldquoOxidation of alco-hols with hydrogen peroxide catalyzed by a new imidazoliumion based phosphotungstate complex in ionic liquidrdquo Journal ofCatalysis vol 230 no 2 pp 436ndash439 2005

[90] J M Tatibouet ldquoMethanol oxidation as a catalytic surfaceproberdquo Applied Catalysis A vol 148 pp 213ndash252 1997

[91] S Ivanova X Nitsch F Romero-Sarria et al ldquoNew class of acidcatalysts for methanol dehydrationrdquo Studies in Surface Scienceand Catalysis vol 175 pp 601ndash604 2010

[92] S Ivanova X Nitsch F Romero-Sarria et al ldquoIonic liquidprotected heteropoly acids for methanol dehydrationrdquoCatalysisToday vol 171 no 1 pp 236ndash241 2011

[93] L Dermeche N Salhi S Hocine R Thouvenot and C RabialdquoEffective Dawson type polyoxometallate catalysts formethanoloxidationrdquo Journal of Molecular Catalysis A vol 356 pp 29ndash352012

[94] N Mizuno K Yamaguchi K Kamata and Y NakagawaldquoMechanismsrdquo inHomogeneous andHeterogeneous EpoxidationCatalysis T Oyama Ed Elsevier B V 2008

[95] Y Roman-Leshkov C J Barrett Z Y Liu and J A DumesicldquoProduction of dimethylfuran for liquid fuels from biomass-derived carbohydratesrdquo Nature vol 447 no 7147 pp 982ndash9852007

[96] B Kamm ldquoProduction of platform chemicals and synthesis gasfrom biomassrdquo Angewandte Chemie International Edition vol46 no 27 pp 5056ndash5058 2007

[97] Q Bao K Qiao D Tomida and C Yokoyama ldquoPreparationof 5-hydroymethylfurfural by dehydration of fructose in thepresence of acidic ionic liquidrdquo Catalysis Communications vol9 no 6 pp 1383ndash1388 2008

[98] C Moreau A Finiels and L Vanoye ldquoDehydration of fructoseand sucrose into 5-hydroxymethylfurfural in the presence of 1-H-3-methyl imidazolium chloride acting both as solvent andcatalystrdquo Journal of Molecular Catalysis A vol 253 no 1-2 pp165ndash169 2006

[99] S Hu Z Zhang Y Zhou et al ldquoConversion of fructose to5-hydroxymethylfurfural using ionic liquids prepared fromrenewable materialsrdquo Green Chemistry vol 10 no 12 pp 1280ndash1283 2008

[100] Q Zhao L Wang S Zhao X Wang and S Wang ldquoHighselective production of 5-hydroymethylfurfural from fructoseby a solid heteropolyacid catalystrdquo Fuel vol 90 no 6 pp 2289ndash2293 2011

International Journal of

AerospaceEngineeringHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

RoboticsJournal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014


Active and Passive Electronic Components

Control Scienceand Engineering

Journal of



RotatingMachinery


Hindawi Publishing Corporation httpwwwhindawicom

Journal ofEngineeringVolume 2014

Submit your manuscripts athttpwwwhindawicom

VLSI Design



Shock and Vibration


Civil EngineeringAdvances in

Acoustics and VibrationAdvances in



Electrical and Computer Engineering

Journal of

Advances inOptoElectronics


Volume 2014

The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

SensorsJournal of


Modelling amp Simulation in EngineeringHindawi Publishing Corporation httpwwwhindawicom Volume 2014


Chemical EngineeringInternational Journal of Antennas and

Propagation




Navigation and Observation



DistributedSensor Networks



(a) (b) (c)

Figure 1 The three main families of polyoxometalates (a) Anderson (XM6O24

119899minus

) (b) Keggin (XM12O40

119899minus

) and (c) Dawson structure(X2M18O62

119899minus

)

050

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013

100150200250300

Figure 2 Number of published articles containing both poly-oxometalates and hybrids according to Science Direct survey inSeptember 2013

properties will not be a subject of this paper this isthe place to highlight the attractive and promisingcharacter of these materials for that kind of applica-tions At the first place the photo- or electrochromicproperties of the POMs depend on their compositionfor example on the components of the materialand on the synergy between them Since the chargetransfer plays a key role in both phenomena it is veryimportant to increase the charge (electrons holesand protons) interactions between the componentseither by introduction of heteroatoms or by the cross-breeding of the organic and inorganic ions in hybridmaterials The progress in this field was summarizedin various works [11ndash17]

Going back to the classification stated above it should bepointed that it is based only on the polyoxoanion whichis generally compensated by the presence of different typeof cations inorganic (H+ Na+ Cs+ etc) or organic Theorganic cations compensation mechanism results in a newclass of hybrid organicinorganic molecular structures Thisability to combine inorganic and organic components at

molecular level provides one of the newest directions inthe material science pointing the possibility of developingmultifunctional materials on the base of properties tuningThe hybrid materials are constructed then in order to takeadvantage of both inorganic (strength thermal stability andchemical resistance) and organic parts (lightness flexibilityand versatility) but with properties independent of thechemical nature of each component but dependent on thesynergism between them [17]

The POMs hybrids field experiences a continuous devel-opment in the last years A simple search in the ScienceDirect database using keywords as ldquopolyoxometalatesrdquo andldquohybridsrdquo shows an almost exponential increase in the last tenyears (Figure 2)

The hybrid organic polyoxometalates can be separatedin two types [1 18] type I hybrids referring to compoundsin which a weak nonbonding interaction between both(inorganic and organic) parts exists (eg electrostatic hydro-gen bonds and van der Waals interactions) and type IIwhere a stronger bonding interaction takes place (covalentor ionocovalent) The type II hybrids group includes all theorganic ligands allowing a direct substitution of oxo groupof the POMs such as alkoxides carboxylates organosylilderivatives and organoamides Extensive reviews on theadvances in the field of type II POMs were reported byDolbecq et al [1] and Gouzerh and Proust [2] and will notbe a subject of this paper On the contrary this review willfocus on POMderivatives involving nonbonding interactionssuch as molecular complexes between polyoxometalates andorganic substrates and more precisely ionic liquids derivedcations forming ionic salts and their application in the fieldof biphasic and heterogeneous catalysis

It is well known that the proton compensated (H+ H3O+

H5O+2 etc) polyoxometalate anions have several advantages

as heterogeneous catalysts such as very strong Bronsted




















R2

R2

R2

R2R2

R3

R3R3

R1 R1

R1

R1

R1

R4R4

N

N+

N+

N+

N+




minus PF6minus BF4

minus etc

P+








3ionic




0

500

1000

1500

2000

2500

3000

3500

4000

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013







1space group




2O (Dmim = 13-


9O34Fe3(1205832-OH)2

(1205833-O)3(WO)

4]sdot05H



6[(AsW

9O33)2(MnIII





C24

C22

C19

C18 C17

C21

C20

C23

Mo4

Mo3

Mo9

Mo6

Mo11

Mo7

Mo1

Mo2

Mo5

Mo8

Mo10

P1

O25

O30

O26

O23

O17

O16

O4

O10

O15

O22

O40

O11

O33

O31

O8

O7

O2

O6

O13

O38

O20 O36

C9

C10

C11

N4

C12

C13

C14

C15

C16

C6

C7

C8

C5

C4

C3

C2

N1

N2

C1

O21

O19

O34

O35

O27

O29

O28

O1

O12

N6

N5







18H37)2N+(CH

3)2]3[PW12O40]

and [(C18H37)N(CH

3)3]4[H2NaPW

10O40] allowing the



c

b a

4877

989

5

(a)

Me

Me

MeMe

Me

MeNNNN

PF6minus SbF6

minus

++

(b)







3[PMo

12O40] for


2Al2O3or TiO





5[PMo





3PW12O40




4SiW12O40





2in very short time







3PW12O40



Table1Summaryof

thep


ppliedin

biph

asicandheterogeneou

scatalysis

Reactio

nMod

elcompo

und

Hybrid

References

Oxidativ

edesulfuriz

ation

Benzothiop

hene

(BT)

5-methylbenzothioph

enes

(5-M

BT)

dibenzothiop

henes(DBT

)Quaternaryam

mon

ium

POMsc

omplexes

[(C 1

8H37) 2N

+ (CH

3)2]

3[PW

12O

40]a

nd[(C 1

8H37)N

(CH

3)3]

4[H

2NaP

W10O

40]

[49ndash

51]


ene

(46-D

MDBT

)+H

2O2andrealdiesel

DBT

+H

2O2

Surfa

ctanttypeP

OMs[(n-C

8H17) 3N(C

H3)

3]3PO

4[XO

(O) 2] 24

[(n-C 1

2H25) 3NCH

3]3PO

4[XO

(O) 2] 24X=MoandW

[5253]

BTD

BT46-D

MDBT

+H

2O2

[Bmim

] 3[PMo 1

2O40](1-b


phosph

omolybdate)

[54]

BTD

BTand46-DMDBT

+H

2O2

[Hmim

] 5[PMo 1

0V2O

40]

[55]

Realdieseloil

[MIM

PS] 3PW

12O

40sdot2H

2O(1-(3-sulfonicg

roup

)propyl-3

-methylimidazolium

phosph

otun

gstate)[Bmim

] 3PW

12O

40(1-bu

tyl3-m

ethylimidazolium

phosph

otun

gstate)[Bmim

] 3PM

o 12O

40[Bmim

] 4SiW

12O

40

[56]

DBT

O+H

2O2

Phosph

otun

gstic

acid

containing

ionicliquidim

mob

ilizedon

magnetic

mesop

orou

ssilica

[57]

Epoxidation

Olefi

ns+H

2O2

Peroxotung

stated

ihydroim

idazolium-based

hybrid

onmod

ified

SiO

2[58]

Methyl-9

10octadecenoate+H

2O2+O

2

Peroxotung

stateimmob

ilizedon

amph

iphilic

resin

usingthem

ethylim

idazolea

ndim

idazoleb

ased

ionicliquids

with

different

alkylsub

stitu

tes(fro

mC 6

toC 1

2)as

alin

kers

[63]

Cyclo

octene

+H

2O2

[[n-C 1

6H33N(C

H3)

3]4N

a 3PW

11O

39]


ledwith

alkylim

idazolium

catio

nsheterop

olytun

gstate-io

nic

liquidm

odified

silicam

agnetitep

articles

[72]

[77]

[78]

Oleicacid

+H

2O2

Q3PO

4[WO(O

2)2]

4(Q

=qu

aternary

ammon

ium)

[76]

Alco

holsoxidation

benzylalcoho

l+H

2O2

H3PW

12O

40on

1-(3-am

inop

ropyl)-3-prop

ylim

idazolium

brom

inem

odified

SBA15

[59]

Varie

tyof

benzylicalcoho

ls+H

2O2

Phosph

otun

gstic


immob

ilizedon

mesop

orou

ssilica

[61]

Varie

tyof


second

aryalcoho

ls1-m

ethyl-3

-butylim

idazolium

decatung

state[bm

im][W

10O

23]

[64]

Benzeneo

xidatio

n+O

2+ascorbicacid

[(C 4

H9)

4N] m[XW

11YO

39H

2O]w

here

X=P5

+ Si

4+G

e4+ B3

+andY=Ti

4+V

5+C

r3+

Mn2

+ Fe

3+C

o2+ Ni2+

Cu2

+ Zn

2+[65]

Methano

l+O

2Bm

im3PMo 1

2O40andBm

im3PW

12O

40[9192]

Hydroxylatio

nBe

nzene+

H2O


iimidazolium)P

Mo 1

0V2O

405minus

[6667]

Esterifi

catio

nPalm

itica

cidto

biod

iesel

Keggin

tung

stoph

osph

atec

omplex

SO3H

functio

nalized

zwitterion

[68]

Varie

tyof

mon

ocarbo

xylic

acidsw

ithmon

ohydric

alcoho

lsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40andalkyl

ammon

ium

[TEA

PS] 3PW

12O

40[6970]

Transeste

rificatio

nTrim

ethylolpropane

+vario

usfatty

acid

methyleste

rsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40and

alkyl

ammon

ium

[TEA

PS] 3PW

12O

40[71]


PW12O3minus40










2O2under O

2flow were found to




10O23] in ionic











3PW12O40 pyridinium


3PW12O40


3PW12O40




16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation




























R2

R2

R2

R2R2

R3

R3R3

R1 R1

R1

R1

R1

R4R4

N

N+

N+

N+

N+




minus PF6minus BF4

minus etc

P+








3ionic




0

500

1000

1500

2000

2500

3000

3500

4000

2000

2001

2002

2003

2004

2005

2006

2007

2008

2009

2010

2011

2012

2013







1space group




2O (Dmim = 13-


9O34Fe3(1205832-OH)2

(1205833-O)3(WO)

4]sdot05H



6[(AsW

9O33)2(MnIII





C24

C22

C19

C18 C17

C21

C20

C23

Mo4

Mo3

Mo9

Mo6

Mo11

Mo7

Mo1

Mo2

Mo5

Mo8

Mo10

P1

O25

O30

O26

O23

O17

O16

O4

O10

O15

O22

O40

O11

O33

O31

O8

O7

O2

O6

O13

O38

O20 O36

C9

C10

C11

N4

C12

C13

C14

C15

C16

C6

C7

C8

C5

C4

C3

C2

N1

N2

C1

O21

O19

O34

O35

O27

O29

O28

O1

O12

N6

N5







18H37)2N+(CH

3)2]3[PW12O40]

and [(C18H37)N(CH

3)3]4[H2NaPW

10O40] allowing the



c

b a

4877

989

5

(a)

Me

Me

MeMe

Me

MeNNNN

PF6minus SbF6

minus

++

(b)







3[PMo

12O40] for


2Al2O3or TiO





5[PMo





3PW12O40




4SiW12O40





2in very short time







3PW12O40



Table1Summaryof

thep


ppliedin

biph

asicandheterogeneou

scatalysis

Reactio

nMod

elcompo

und

Hybrid

References

Oxidativ

edesulfuriz

ation

Benzothiop

hene

(BT)

5-methylbenzothioph

enes

(5-M

BT)

dibenzothiop

henes(DBT

)Quaternaryam

mon

ium

POMsc

omplexes

[(C 1

8H37) 2N

+ (CH

3)2]

3[PW

12O

40]a

nd[(C 1

8H37)N

(CH

3)3]

4[H

2NaP

W10O

40]

[49ndash

51]


ene

(46-D

MDBT

)+H

2O2andrealdiesel

DBT

+H

2O2

Surfa

ctanttypeP

OMs[(n-C

8H17) 3N(C

H3)

3]3PO

4[XO

(O) 2] 24

[(n-C 1

2H25) 3NCH

3]3PO

4[XO

(O) 2] 24X=MoandW

[5253]

BTD

BT46-D

MDBT

+H

2O2

[Bmim

] 3[PMo 1

2O40](1-b


phosph

omolybdate)

[54]

BTD

BTand46-DMDBT

+H

2O2

[Hmim

] 5[PMo 1

0V2O

40]

[55]

Realdieseloil

[MIM

PS] 3PW

12O

40sdot2H

2O(1-(3-sulfonicg

roup

)propyl-3

-methylimidazolium

phosph

otun

gstate)[Bmim

] 3PW

12O

40(1-bu

tyl3-m

ethylimidazolium

phosph

otun

gstate)[Bmim

] 3PM

o 12O

40[Bmim

] 4SiW

12O

40

[56]

DBT

O+H

2O2

Phosph

otun

gstic

acid

containing

ionicliquidim

mob

ilizedon

magnetic

mesop

orou

ssilica

[57]

Epoxidation

Olefi

ns+H

2O2

Peroxotung

stated

ihydroim

idazolium-based

hybrid

onmod

ified

SiO

2[58]

Methyl-9

10octadecenoate+H

2O2+O

2

Peroxotung

stateimmob

ilizedon

amph

iphilic

resin

usingthem

ethylim

idazolea

ndim

idazoleb

ased

ionicliquids

with

different

alkylsub

stitu

tes(fro

mC 6

toC 1

2)as

alin

kers

[63]

Cyclo

octene

+H

2O2

[[n-C 1

6H33N(C

H3)

3]4N

a 3PW

11O

39]


ledwith

alkylim

idazolium

catio

nsheterop

olytun

gstate-io

nic

liquidm

odified

silicam

agnetitep

articles

[72]

[77]

[78]

Oleicacid

+H

2O2

Q3PO

4[WO(O

2)2]

4(Q

=qu

aternary

ammon

ium)

[76]

Alco

holsoxidation

benzylalcoho

l+H

2O2

H3PW

12O

40on

1-(3-am

inop

ropyl)-3-prop

ylim

idazolium

brom

inem

odified

SBA15

[59]

Varie

tyof

benzylicalcoho

ls+H

2O2

Phosph

otun

gstic


immob

ilizedon

mesop

orou

ssilica

[61]

Varie

tyof


second

aryalcoho

ls1-m

ethyl-3

-butylim

idazolium

decatung

state[bm

im][W

10O

23]

[64]

Benzeneo

xidatio

n+O

2+ascorbicacid

[(C 4

H9)

4N] m[XW

11YO

39H

2O]w

here

X=P5

+ Si

4+G

e4+ B3

+andY=Ti

4+V

5+C

r3+

Mn2

+ Fe

3+C

o2+ Ni2+

Cu2

+ Zn

2+[65]

Methano

l+O

2Bm

im3PMo 1

2O40andBm

im3PW

12O

40[9192]

Hydroxylatio

nBe

nzene+

H2O


iimidazolium)P

Mo 1

0V2O

405minus

[6667]

Esterifi

catio

nPalm

itica

cidto

biod

iesel

Keggin

tung

stoph

osph

atec

omplex

SO3H

functio

nalized

zwitterion

[68]

Varie

tyof

mon

ocarbo

xylic

acidsw

ithmon

ohydric

alcoho

lsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40andalkyl

ammon

ium

[TEA

PS] 3PW

12O

40[6970]

Transeste

rificatio

nTrim

ethylolpropane

+vario

usfatty

acid

methyleste

rsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40and

alkyl

ammon

ium

[TEA

PS] 3PW

12O

40[71]


PW12O3minus40










2O2under O

2flow were found to




10O23] in ionic











3PW12O40 pyridinium


3PW12O40


3PW12O40




16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










C24

C22

C19

C18 C17

C21

C20

C23

Mo4

Mo3

Mo9

Mo6

Mo11

Mo7

Mo1

Mo2

Mo5

Mo8

Mo10

P1

O25

O30

O26

O23

O17

O16

O4

O10

O15

O22

O40

O11

O33

O31

O8

O7

O2

O6

O13

O38

O20 O36

C9

C10

C11

N4

C12

C13

C14

C15

C16

C6

C7

C8

C5

C4

C3

C2

N1

N2

C1

O21

O19

O34

O35

O27

O29

O28

O1

O12

N6

N5







18H37)2N+(CH

3)2]3[PW12O40]

and [(C18H37)N(CH

3)3]4[H2NaPW

10O40] allowing the



c

b a

4877

989

5

(a)

Me

Me

MeMe

Me

MeNNNN

PF6minus SbF6

minus

++

(b)







3[PMo

12O40] for


2Al2O3or TiO





5[PMo





3PW12O40




4SiW12O40





2in very short time







3PW12O40



Table1Summaryof

thep


ppliedin

biph

asicandheterogeneou

scatalysis

Reactio

nMod

elcompo

und

Hybrid

References

Oxidativ

edesulfuriz

ation

Benzothiop

hene

(BT)

5-methylbenzothioph

enes

(5-M

BT)

dibenzothiop

henes(DBT

)Quaternaryam

mon

ium

POMsc

omplexes

[(C 1

8H37) 2N

+ (CH

3)2]

3[PW

12O

40]a

nd[(C 1

8H37)N

(CH

3)3]

4[H

2NaP

W10O

40]

[49ndash

51]


ene

(46-D

MDBT

)+H

2O2andrealdiesel

DBT

+H

2O2

Surfa

ctanttypeP

OMs[(n-C

8H17) 3N(C

H3)

3]3PO

4[XO

(O) 2] 24

[(n-C 1

2H25) 3NCH

3]3PO

4[XO

(O) 2] 24X=MoandW

[5253]

BTD

BT46-D

MDBT

+H

2O2

[Bmim

] 3[PMo 1

2O40](1-b


phosph

omolybdate)

[54]

BTD

BTand46-DMDBT

+H

2O2

[Hmim

] 5[PMo 1

0V2O

40]

[55]

Realdieseloil

[MIM

PS] 3PW

12O

40sdot2H

2O(1-(3-sulfonicg

roup

)propyl-3

-methylimidazolium

phosph

otun

gstate)[Bmim

] 3PW

12O

40(1-bu

tyl3-m

ethylimidazolium

phosph

otun

gstate)[Bmim

] 3PM

o 12O

40[Bmim

] 4SiW

12O

40

[56]

DBT

O+H

2O2

Phosph

otun

gstic

acid

containing

ionicliquidim

mob

ilizedon

magnetic

mesop

orou

ssilica

[57]

Epoxidation

Olefi

ns+H

2O2

Peroxotung

stated

ihydroim

idazolium-based

hybrid

onmod

ified

SiO

2[58]

Methyl-9

10octadecenoate+H

2O2+O

2

Peroxotung

stateimmob

ilizedon

amph

iphilic

resin

usingthem

ethylim

idazolea

ndim

idazoleb

ased

ionicliquids

with

different

alkylsub

stitu

tes(fro

mC 6

toC 1

2)as

alin

kers

[63]

Cyclo

octene

+H

2O2

[[n-C 1

6H33N(C

H3)

3]4N

a 3PW

11O

39]


ledwith

alkylim

idazolium

catio

nsheterop

olytun

gstate-io

nic

liquidm

odified

silicam

agnetitep

articles

[72]

[77]

[78]

Oleicacid

+H

2O2

Q3PO

4[WO(O

2)2]

4(Q

=qu

aternary

ammon

ium)

[76]

Alco

holsoxidation

benzylalcoho

l+H

2O2

H3PW

12O

40on

1-(3-am

inop

ropyl)-3-prop

ylim

idazolium

brom

inem

odified

SBA15

[59]

Varie

tyof

benzylicalcoho

ls+H

2O2

Phosph

otun

gstic


immob

ilizedon

mesop

orou

ssilica

[61]

Varie

tyof


second

aryalcoho

ls1-m

ethyl-3

-butylim

idazolium

decatung

state[bm

im][W

10O

23]

[64]

Benzeneo

xidatio

n+O

2+ascorbicacid

[(C 4

H9)

4N] m[XW

11YO

39H

2O]w

here

X=P5

+ Si

4+G

e4+ B3

+andY=Ti

4+V

5+C

r3+

Mn2

+ Fe

3+C

o2+ Ni2+

Cu2

+ Zn

2+[65]

Methano

l+O

2Bm

im3PMo 1

2O40andBm

im3PW

12O

40[9192]

Hydroxylatio

nBe

nzene+

H2O


iimidazolium)P

Mo 1

0V2O

405minus

[6667]

Esterifi

catio

nPalm

itica

cidto

biod

iesel

Keggin

tung

stoph

osph

atec

omplex

SO3H

functio

nalized

zwitterion

[68]

Varie

tyof

mon

ocarbo

xylic

acidsw

ithmon

ohydric

alcoho

lsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40andalkyl

ammon

ium

[TEA

PS] 3PW

12O

40[6970]

Transeste

rificatio

nTrim

ethylolpropane

+vario

usfatty

acid

methyleste

rsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40and

alkyl

ammon

ium

[TEA

PS] 3PW

12O

40[71]


PW12O3minus40










2O2under O

2flow were found to




10O23] in ionic











3PW12O40 pyridinium


3PW12O40


3PW12O40




16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










c

b a

4877

989

5

(a)

Me

Me

MeMe

Me

MeNNNN

PF6minus SbF6

minus

++

(b)







3[PMo

12O40] for


2Al2O3or TiO





5[PMo





3PW12O40




4SiW12O40





2in very short time







3PW12O40



Table1Summaryof

thep


ppliedin

biph

asicandheterogeneou

scatalysis

Reactio

nMod

elcompo

und

Hybrid

References

Oxidativ

edesulfuriz

ation

Benzothiop

hene

(BT)

5-methylbenzothioph

enes

(5-M

BT)

dibenzothiop

henes(DBT

)Quaternaryam

mon

ium

POMsc

omplexes

[(C 1

8H37) 2N

+ (CH

3)2]

3[PW

12O

40]a

nd[(C 1

8H37)N

(CH

3)3]

4[H

2NaP

W10O

40]

[49ndash

51]


ene

(46-D

MDBT

)+H

2O2andrealdiesel

DBT

+H

2O2

Surfa

ctanttypeP

OMs[(n-C

8H17) 3N(C

H3)

3]3PO

4[XO

(O) 2] 24

[(n-C 1

2H25) 3NCH

3]3PO

4[XO

(O) 2] 24X=MoandW

[5253]

BTD

BT46-D

MDBT

+H

2O2

[Bmim

] 3[PMo 1

2O40](1-b


phosph

omolybdate)

[54]

BTD

BTand46-DMDBT

+H

2O2

[Hmim

] 5[PMo 1

0V2O

40]

[55]

Realdieseloil

[MIM

PS] 3PW

12O

40sdot2H

2O(1-(3-sulfonicg

roup

)propyl-3

-methylimidazolium

phosph

otun

gstate)[Bmim

] 3PW

12O

40(1-bu

tyl3-m

ethylimidazolium

phosph

otun

gstate)[Bmim

] 3PM

o 12O

40[Bmim

] 4SiW

12O

40

[56]

DBT

O+H

2O2

Phosph

otun

gstic

acid

containing

ionicliquidim

mob

ilizedon

magnetic

mesop

orou

ssilica

[57]

Epoxidation

Olefi

ns+H

2O2

Peroxotung

stated

ihydroim

idazolium-based

hybrid

onmod

ified

SiO

2[58]

Methyl-9

10octadecenoate+H

2O2+O

2

Peroxotung

stateimmob

ilizedon

amph

iphilic

resin

usingthem

ethylim

idazolea

ndim

idazoleb

ased

ionicliquids

with

different

alkylsub

stitu

tes(fro

mC 6

toC 1

2)as

alin

kers

[63]

Cyclo

octene

+H

2O2

[[n-C 1

6H33N(C

H3)

3]4N

a 3PW

11O

39]


ledwith

alkylim

idazolium

catio

nsheterop

olytun

gstate-io

nic

liquidm

odified

silicam

agnetitep

articles

[72]

[77]

[78]

Oleicacid

+H

2O2

Q3PO

4[WO(O

2)2]

4(Q

=qu

aternary

ammon

ium)

[76]

Alco

holsoxidation

benzylalcoho

l+H

2O2

H3PW

12O

40on

1-(3-am

inop

ropyl)-3-prop

ylim

idazolium

brom

inem

odified

SBA15

[59]

Varie

tyof

benzylicalcoho

ls+H

2O2

Phosph

otun

gstic


immob

ilizedon

mesop

orou

ssilica

[61]

Varie

tyof


second

aryalcoho

ls1-m

ethyl-3

-butylim

idazolium

decatung

state[bm

im][W

10O

23]

[64]

Benzeneo

xidatio

n+O

2+ascorbicacid

[(C 4

H9)

4N] m[XW

11YO

39H

2O]w

here

X=P5

+ Si

4+G

e4+ B3

+andY=Ti

4+V

5+C

r3+

Mn2

+ Fe

3+C

o2+ Ni2+

Cu2

+ Zn

2+[65]

Methano

l+O

2Bm

im3PMo 1

2O40andBm

im3PW

12O

40[9192]

Hydroxylatio

nBe

nzene+

H2O


iimidazolium)P

Mo 1

0V2O

405minus

[6667]

Esterifi

catio

nPalm

itica

cidto

biod

iesel

Keggin

tung

stoph

osph

atec

omplex

SO3H

functio

nalized

zwitterion

[68]

Varie

tyof

mon

ocarbo

xylic

acidsw

ithmon

ohydric

alcoho

lsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40andalkyl

ammon

ium

[TEA

PS] 3PW

12O

40[6970]

Transeste

rificatio

nTrim

ethylolpropane

+vario

usfatty

acid

methyleste

rsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40and

alkyl

ammon

ium

[TEA

PS] 3PW

12O

40[71]


PW12O3minus40










2O2under O

2flow were found to




10O23] in ionic











3PW12O40 pyridinium


3PW12O40


3PW12O40




16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










Table1Summaryof

thep


ppliedin

biph

asicandheterogeneou

scatalysis

Reactio

nMod

elcompo

und

Hybrid

References

Oxidativ

edesulfuriz

ation

Benzothiop

hene

(BT)

5-methylbenzothioph

enes

(5-M

BT)

dibenzothiop

henes(DBT

)Quaternaryam

mon

ium

POMsc

omplexes

[(C 1

8H37) 2N

+ (CH

3)2]

3[PW

12O

40]a

nd[(C 1

8H37)N

(CH

3)3]

4[H

2NaP

W10O

40]

[49ndash

51]


ene

(46-D

MDBT

)+H

2O2andrealdiesel

DBT

+H

2O2

Surfa

ctanttypeP

OMs[(n-C

8H17) 3N(C

H3)

3]3PO

4[XO

(O) 2] 24

[(n-C 1

2H25) 3NCH

3]3PO

4[XO

(O) 2] 24X=MoandW

[5253]

BTD

BT46-D

MDBT

+H

2O2

[Bmim

] 3[PMo 1

2O40](1-b


phosph

omolybdate)

[54]

BTD

BTand46-DMDBT

+H

2O2

[Hmim

] 5[PMo 1

0V2O

40]

[55]

Realdieseloil

[MIM

PS] 3PW

12O

40sdot2H

2O(1-(3-sulfonicg

roup

)propyl-3

-methylimidazolium

phosph

otun

gstate)[Bmim

] 3PW

12O

40(1-bu

tyl3-m

ethylimidazolium

phosph

otun

gstate)[Bmim

] 3PM

o 12O

40[Bmim

] 4SiW

12O

40

[56]

DBT

O+H

2O2

Phosph

otun

gstic

acid

containing

ionicliquidim

mob

ilizedon

magnetic

mesop

orou

ssilica

[57]

Epoxidation

Olefi

ns+H

2O2

Peroxotung

stated

ihydroim

idazolium-based

hybrid

onmod

ified

SiO

2[58]

Methyl-9

10octadecenoate+H

2O2+O

2

Peroxotung

stateimmob

ilizedon

amph

iphilic

resin

usingthem

ethylim

idazolea

ndim

idazoleb

ased

ionicliquids

with

different

alkylsub

stitu

tes(fro

mC 6

toC 1

2)as

alin

kers

[63]

Cyclo

octene

+H

2O2

[[n-C 1

6H33N(C

H3)

3]4N

a 3PW

11O

39]


ledwith

alkylim

idazolium

catio

nsheterop

olytun

gstate-io

nic

liquidm

odified

silicam

agnetitep

articles

[72]

[77]

[78]

Oleicacid

+H

2O2

Q3PO

4[WO(O

2)2]

4(Q

=qu

aternary

ammon

ium)

[76]

Alco

holsoxidation

benzylalcoho

l+H

2O2

H3PW

12O

40on

1-(3-am

inop

ropyl)-3-prop

ylim

idazolium

brom

inem

odified

SBA15

[59]

Varie

tyof

benzylicalcoho

ls+H

2O2

Phosph

otun

gstic


immob

ilizedon

mesop

orou

ssilica

[61]

Varie

tyof


second

aryalcoho

ls1-m

ethyl-3

-butylim

idazolium

decatung

state[bm

im][W

10O

23]

[64]

Benzeneo

xidatio

n+O

2+ascorbicacid

[(C 4

H9)

4N] m[XW

11YO

39H

2O]w

here

X=P5

+ Si

4+G

e4+ B3

+andY=Ti

4+V

5+C

r3+

Mn2

+ Fe

3+C

o2+ Ni2+

Cu2

+ Zn

2+[65]

Methano

l+O

2Bm

im3PMo 1

2O40andBm

im3PW

12O

40[9192]

Hydroxylatio

nBe

nzene+

H2O


iimidazolium)P

Mo 1

0V2O

405minus

[6667]

Esterifi

catio

nPalm

itica

cidto

biod

iesel

Keggin

tung

stoph

osph

atec

omplex

SO3H

functio

nalized

zwitterion

[68]

Varie

tyof

mon

ocarbo

xylic

acidsw

ithmon

ohydric

alcoho

lsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40andalkyl

ammon

ium

[TEA

PS] 3PW

12O

40[6970]

Transeste

rificatio

nTrim

ethylolpropane

+vario

usfatty

acid

methyleste

rsIm

idazolium

based[M

IMPS

] 3PW

12O

40pyridinium

based-[PyP

S]3PW

12O

40and

alkyl

ammon

ium

[TEA

PS] 3PW

12O

40[71]


PW12O3minus40










2O2under O

2flow were found to




10O23] in ionic











3PW12O40 pyridinium


3PW12O40


3PW12O40




16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










PW12O3minus40










2O2under O

2flow were found to




10O23] in ionic











3PW12O40 pyridinium


3PW12O40


3PW12O40




16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











16H33N(CH





4[(WO(O









6






7H15)4N]6[120572-SiW

11O39Co]

and [(n-C7H15)4N]6[120572-SiW








2O2over





0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation










0 5 10 15 20 25 300

10

20

30

40

50

60

70

80

90

100

DM

E yi

eld

()

Time (h)

Bmim3PMo12O40

Bmim3PW12O40

Cs2HPW12O40



3PMo12O40



2HPW

12O40



Where Is the Future









References























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation



























































18H37N(CH

3)3]4[H2NaPW

10O36]

















2O2mediated




























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation
























5

H5N+(CH


and [p-C5H5N+(CH

2)15

CH3]3PO4[M(O)(O





















RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation











RoboticsJournal of





Journal of



RotatingMachinery





VLSI Design



Shock and Vibration







Journal of



Volume 2014


SensorsJournal of





Propagation









review article hybrid organic-inorganic materials based on...

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