general seminar 2009.pptx
TRANSCRIPT
-
8/14/2019 GENERAL SEMINAR 2009.pptx
1/45
One Dimensional Assemblies of
Nanoparticles
Pratheesh V. Nair
Photosciences & Photonics Group
Chemical Sciences and Technology Division
NIIST (CSIR)
Trivandrum
-
8/14/2019 GENERAL SEMINAR 2009.pptx
2/45
Introduction to nanoscale assemblies
One dimensional assemblies; preparation methods
Properties and applications
Future perspectives
Conclusion
-
8/14/2019 GENERAL SEMINAR 2009.pptx
3/45
What is nano ?
Nanomater ials
Def ini t ion :- Part ic les of any matter having on e of its dimension s in the range1-100 nm
Capabilityto manipulate, control, assemble, produce
and manufacture things at atomicprecision
The prefix nano- comes from the Greek word for dwarf.
In science, nano means a measure of 10-9units.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
4/45
Importance-
Exhibit characteristic physical and chemical properties different from that
of bulk
Properties can be tailored by varying their size and shape
For any application their integration into higher order assemblies is essential
Nanoscience and nanotechnology pertain to the synthesis, characterization,
exploration, integration and utilization of materials, which are characterized by
at least one dimension in the nanometer (1 nm = 10-9m) range
-
8/14/2019 GENERAL SEMINAR 2009.pptx
5/45
Nanoscale Building Blocks
Metal Nanostructures (Au, Ag, Cu, Pt, Pd )
Semiconductor Nanostructures (CdS, CdSe, CdTe InP, GaN)
Carbon Nanostructures (CNTs, Fullerenes, Graphene )
Quantum Dots
Quantum Rods Fullerene clusters
Carbon nanotubes
20 nm
u Nanorods
20 nm
g Nanoprisms
-
8/14/2019 GENERAL SEMINAR 2009.pptx
6/45
Where are we now ?
-
8/14/2019 GENERAL SEMINAR 2009.pptx
7/45
Current research on nanoparticles can be classified into two main trends
Manipulation and exploration of single NPs in devices thus reaching the
limit of miniaturization possible for electronic circuits.
Application of NPs/polymer composites as macroscale thin films
producing a new generation of currently using devices.
Angew. Chem. Int. Ed. 2006,45,5796
Nano LEDs
Quantum dot Solar cells
J. Am. Chem. Soc. 2006,128, 1385
J. Am. Chem. Soc. 2006, 128, 2115.
Bio-imaging
Paper batteries
PNAS, 2007, 104, 13574.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
8/45
How can we integrate nanomaterials into higher order structures having
well defined size, shape and function ?
they prov ide direct br idges between nanometer scale ob jects and
macroscale wo r ld
can play cr i t ical roles in the impro vement o f eff ic iencies of var ious
dev ices b ased o n n anopar tic les and their composi tes
can help in the und ers tanding of v arious b io logical processes and
quantum mechanical concepts
Top dow n
Lithography
Stamping (microcontact
printing)
Bot tom up
Self-assembly
Template assisted
Why nanoscale assemblies ?
-
8/14/2019 GENERAL SEMINAR 2009.pptx
9/45
Nanoparticle assemblies can be classified into three categories ;
Techniques for 2D and 3D NP assemblies;
a)SolventEvaporation b)LangmuirBlodgettTransfer c)Layerbylayerassembly
a) One dimensional (1 D)
b) Two dimensional ( 2 D)
c) Three dimensional (3 D)
-
8/14/2019 GENERAL SEMINAR 2009.pptx
10/45
Solvent Evaporation
The relatively weak attractions between nanocrystals, which are efficiently screened in
solution, become manifest as the solvent evaporates, initiating assembly of intricate,
slowly evolving structures.
J. Colloid Interface Sci.2006, 301,703.Dissipative dewetting followed byself-assembly of NPs
TEM images of nanoparticle aggregates
after solvent evaporation
-
8/14/2019 GENERAL SEMINAR 2009.pptx
11/45
Langmuir Blodgett Transfer
Generally, a LangmuirBlodgett film contains one or more monolayers of an organic
material, deposited from the surface of a liquid onto a solid by immersing (or emersing)
the solid substrate into (or from) the liquid.
Well ordered ultra thin films
Direct detection of defects/cracks on surface
layer stability and contamination..!
-
8/14/2019 GENERAL SEMINAR 2009.pptx
12/45
Layer by layer assembly
Layer-by-layer (LBL) assembly is a simple and versatile method for material design
with nanometer scale control over internal architecture
Device fabrication
Functional Coatings
Biomedical Applications
Scheme of the LBL film-deposition
Steps 1 and 3 represent the adsorption of polyanion
and polycation, steps 2 and 4 are washing steps.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
13/45
1-D assemblies of NPs: Preparation methods
Lineartemplate
method
Preparation methods
Selfassembly
method
Polyelectrolytes
biomolecules
InorganicNWsandtubes
Othertemplates
Magnetic
dipole moment
Electric dipole moment
Oriented attachment
Hydrogen Bonding
-
8/14/2019 GENERAL SEMINAR 2009.pptx
14/45
Lineartemplate method
Directional organization ; critical step for the fabrication of 1 D assemblies
Soft templatesOrganic Polyelectrolytes and biomolecules
Hard templates Inorganic nanotubes and nanowires
Polyelectrolytes are polymers whose repeat ing
units bear an electrolyte group ; Dissociates in
aqueous solut ion s, making the polymers charged.
Polystyrene sulfonate (PSS)
How they act ?
Act as a scaffold for the adsorption of metal ions with opposite charges
Ion adsorbed polyelectrolyte templates can transform to 1 D NP assemblies
http://upload.wikimedia.org/wikipedia/en/3/32/Polyelectrolyte_examples.png -
8/14/2019 GENERAL SEMINAR 2009.pptx
15/45
Mineralization of Single Flexible Polyelectrolyte Molecules
Minko et al, J. Am. Chem.Soc. 2002,124,10192.
Poly(2-vinylpyridine) (P2VP) was deposited on the surface of Si-wafer or mica in
different conformations from an elongated wormlike coil to compact globule.
AFM images of various conformations of P2VP
molecules on a solid substrate
Poly(2-vinylpyr idine) (P2VP)
conformational transitions from stretched wormlike coil to necklace-likeglobule, and to compact globule
the fraction of charged monomers decreases with an increase of pH and ionicstrength.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
16/45
Mineralization of PE
Electrostatic adsorption of PdCl42-
onto cationic P2VP chains
Reduction with dimethylamine
borane to get Pd NP assemblies
Cross-section profiles of Pd-nanowiresAFM images of Pd NP decorated PE chains
( single Pd nanoparticles are visible )
-
8/14/2019 GENERAL SEMINAR 2009.pptx
17/45
Biomolecules as templates
A perfect choice for 1 D assembly of nanoparticles !!!!!
The versatility of experimental methods for the manipulation of their structure
Excellent experimental foundation for such studies developed in the life-science field
Biological templates, such as DNA, protein cages, viroid capsules, bacterial
rhapidosomes, multicellular superstructures, biolipid Cylinders, linear fibrous
biomacromolecules like fibrin, dextran and collagen have been utilized to direct
the deposition, assembly, and patterning of inorganic nanoparticles and
microstructures.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
18/45
DNA: A Programmable Nanoscale Assembly Material
Attractive Nanomaterial Properties of DNA:
Strong electrostatic and coordination interactions with metal nanoparticles
Synthetic versatility: vary length, sequence, backbone, branched
Easily modified for conjugation to molecules, nanoparticles
DNA-linked nanoparticles
100 nm
Chem. Mater.2005, 17, 1628.
Science, 2003, 302 , 1545.
DNA-wrapped CNTs
Inorg. Chem. 2000,39, 2258.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
19/45
Linear Assemblies of Nanoparticles Electrostatically Organized on DNA Scaffolds
Warner et al,Nat. Mater. 2003, 2, 272-277.
Electrostatic assembly of cationic NPs onto the anionic backbone of DNA
Wide range of structures including closely spaced linear arrays, ribbons or
bundles and branched assemblies.
linear arrays
ribbons or bundles
branched
assemblies
-
8/14/2019 GENERAL SEMINAR 2009.pptx
20/45
Monitoring the assembly process
in solution by UV-Vis spectroscopy
Precipitation of the hybridsystem as a function of time
Linear arrays Ribbons or bundles Branched assemblies
-
8/14/2019 GENERAL SEMINAR 2009.pptx
21/45
Au Nanocrystal Growth on Nanotubes Controlled by Conformations
and Charges of Sequenced Peptide Templates
Matsui et al, J. Am. Chem.Soc. 2003,125,5873.
Self-assembly of bis(N-R-amid o-glyc ylg lycin e)-1,7-heptane dic arbox ylatemolecules into nanowires.
Immobilization of a histidine-rich peptide on the nanowires at the binding sites.
Addition of Au salt into nanowire solution and reduction using hydrazine hydrate
bis(N-R-amido-glycylglycine)-1,7-
heptane dicarboxylate
Scheme of the Au nanowire fabrication
A-H-H-A-H-H-A-A-D
-
8/14/2019 GENERAL SEMINAR 2009.pptx
22/45
The Influence of pH upon Au Nanocrystal Growth
Higher packing density at higher pH
43 %
78 %
pH - 8 pH - 12
packing density increases
with incubation time
i d b
-
8/14/2019 GENERAL SEMINAR 2009.pptx
23/45
Inorganic NWs and Nanotubes
Preparation methods can be classified into three
1, Direct chemical deposition
2, Sol-gel decoration
3, Specific adsorption
Known as hard templates
most common templates are carbon nanotubes
Greater hardness and toughness ; preservation of structure and shape intact
Nature.1993
, 361,333
.
Adv. Mater., 2000, 19, 1430.
Chem. Mater., 2001, 13, 2864.
Nano Lett. 2003, 3, 723.
J. Phys. Chem. C. 2003, 107, 2453.
Chem. Eur. J., 2003, 9, 1898.
Nano L ett. 2004, 4, 225.
Science 2004, 304, 1787.
Adv. Mater., 2004, 16, 929.
Nano Lett. 2002, 2, 1253.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
24/45
Aligning Au Nanorods by Using Carbon Nanotubes as Templates
Liz-Marzan et al, Angew. Chem. Int. Ed. 2005,44,4375.
uniform electrostatic assembly of Au nanorods on MWNTs
rods form strings with end-to-end contacts
uniaxial plasmon coupling
TEM images of Au assembled on
MWNTs (average diameter 30 nm) Surface plasmon coupling in Au nanorods
-
8/14/2019 GENERAL SEMINAR 2009.pptx
25/45
-
8/14/2019 GENERAL SEMINAR 2009.pptx
26/45
Brust. M and co workers, Adv. Mater. 2001,13,1800.
Template ; a corrugated thin film of amorphous carbon withtopographical features of nanometer dimensions.
PTFE lines on a
glass substrate
Vapour deposition
of carbon filmCarbon
replica
Au NP
solution
Evaporation Self-assembly of
Au NPs in rows
Templated Gold Nanowire Self-Assembly on Carbon Substrates
AFM image of PTFElines on glass substrate
TEM image of self-assembled
lines of Au NPs on carbon
replica
Au nanowire obtained after
heat treatment
Template Free Self Assembly method
-
8/14/2019 GENERAL SEMINAR 2009.pptx
27/45
Template- Free, Self - Assembly method
1. Templates may affect the properties of nanoparticle assemblies.
2. Removal of templates is not easy.
3. Morphological or structural alterations to the NP chains.
Demerits of template assisted synthesis
Magnetic Dipole Moments
The magnetic NPs can self-assemble into one-dimensional chains onsubstrates and in colloid dispersions through magnetic dipolarinteraction without the help of an applied magnetic field.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
28/45
Chain formation and anisotropy of magnetic NPs have been well-known in nature
TEM image of a magnetotactic bacterium,
Desulfovibrio magneticus strain RS-1, showing
a chain of bullet-shaped magnetosomes aligned
along the Earth's magnetic field.
agnetotactic bacterium a biological compass
Tokyo University of Agricultur e and Technology
Magnetosomes ineukaryotic algaeNP chains in frontaltissues of Chinook salmonMagnetoSpirillum MS-1)
-
8/14/2019 GENERAL SEMINAR 2009.pptx
29/45
Self-Assembly of iron oxide nanoparticles through magnetic dipole interactions
Zhang et al, J. Phys. Chem. C. 2008,112,15151.
Magnetic dipole interactions in weakly ferromagnetic nanoparticles
Under an applied magnetic field, the nanostructures can be oriented aligning
with the external magnetic field.
TEM images of aligned nanoparticles
Electric Dipole Moments
-
8/14/2019 GENERAL SEMINAR 2009.pptx
30/45
Electric Dipole Moments
prevalent in semiconductor nanoparticles due to either the presence of an
anisotropic crystal lattice or surface defects.
Strong electrostatic or steric repulsion from stabilizers overcompensates
electric-dipole attractions between NPs.
Repulsive forces electrostatic interactions
VT= VA+ VR
VA= -A/(12 D2) - attractive forces
VR= 2 a 2exp(-D) - repulsive forces
DLVO Theory
Attractive forces van der Waals
interactions and dipoledipole interactions
-
8/14/2019 GENERAL SEMINAR 2009.pptx
31/45
How to overcome the repulsion..? Partial removal of the stabilizer !!!
Organization of CdTe NPs into nanowires upon partial removal of the of organic stabilizer
Kotov and co workers, Science, 2002, 297, 237.
CdTe quantum dot to nanowire transformation in phosphate buffer solution
Rogach and co workers, J. Phys. Chem. C. 2007,111,18927.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
32/45
Hydrazine
Ligand removal
CdTe QDS CdTe nanowire
Hydrazine induced one dimensional organization of CdTe QDs
Hydrazine is a Bronsted base and can gently react to remove the capping ligands from the
nanocrystal surface.
Hydrazine is a reducing agent, preventing oxidation of QD surface and repairing any
oxidized tellurium surface sites.
Pratheesh V. Nair and K. George Thomas J. Phys. Chem. Lett. 2010
O i t d A ti
-
8/14/2019 GENERAL SEMINAR 2009.pptx
33/45
Oriented Aggregation
Oriented aggregation is a special case of aggregation that provides an important
route by which nanocrystals grow and unique, often symmetry-defying, crystal
morphologies are produced.
Oriented attachment may occur by
collisions of aligned nanocrystals in suspension
or
rotation of misaligned NPs in contact toward low-energy interface configurations
Oriented
attachment
1 D
growth
misaligned NPs aligned NPsNanowires
Formation of Ag nanowires from Ag NPs through oriented attachment
-
8/14/2019 GENERAL SEMINAR 2009.pptx
34/45
Formation of Ag nanowires from Ag NPs through oriented attachment
Liz-Marzan et al, J. Mater. Chem. 2004,14,607.
Evidence of an aggregative mechanism during the formation of silver nanowires in DMF
HRTEM images showing the various steps during the formation of Ag
nanowires from individual Ag nanoparticles
Formation of Ag nanowires by solvent reduction in DMF, in the presence of
poly(vinylpyrrolidone) (PVP) at high temperature
Self Assembly of ZnO: From Nanodots to Nanorods
-
8/14/2019 GENERAL SEMINAR 2009.pptx
35/45
Self-Assembly of ZnO: From Nanodots to Nanorods
Weller et al, Angew. Chem. Int. Ed. 2002,41,1188.
Formation of high-quality single crystalline ZnO nanorods from spherical ZnO
nanoparticles through oriented attachment.
lattice planes go straight through the contact areas
particles are epitaxially fused together
bottlenecks between the adjacent particles are still visible
individual nanoparticles aligned nanoparticles nanorods
Hydrogen Bonding
http://en.wikipedia.org/wiki/File:3D_model_hydrogen_bonds_in_water.jpg -
8/14/2019 GENERAL SEMINAR 2009.pptx
36/45
Hydrogen Bonding
A hydrogen bond is the attractive force between the hydrogen
attached to an electronegative atom of one molecule and an
electronegative atom of a different molecule.
Hydrogen-Bonding-Assisted Self-Assembly of polymers
J. Am. Chem. Soc. 2009,131, 13594 Langmuir, 2008, 24, 7727.
U i i l Pl C li th h L it di l S lf A bl f G ld N d
http://pubs.acs.org/action/showImage?doi=10.1021/ja905240w&iName=master.img-001.jpg&type=masterhttp://en.wikipedia.org/wiki/File:3D_model_hydrogen_bonds_in_water.jpg -
8/14/2019 GENERAL SEMINAR 2009.pptx
37/45
Uniaxial Plasmon Coupling through Longitudinal Self-Assembly of Gold Nanorods
George Thomas and co workers, J. Phys. Chem. B. 2004,108,13066.
Absorption spectra of gold nanorods
recorded immediately after the
addition of MPA
Properties and applications
-
8/14/2019 GENERAL SEMINAR 2009.pptx
38/45
p pp
1D NP assemblies exhibit many collective properties, which are evidently
different from single NPs.
Drastic effects on the optical response from surface plasmon absorption is
found when metallic NPs form rods, chains or sheets
Time-dependent optical studies to elucidate the mechanism of chain self-assembly
Decrease in intensity of surface plasmon band at 520 nm and formation of a shoulder at
higher wavelength
Adv. Mater. 2005,17, 2553.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
39/45
One-Dimensional Energy Transfer in CdTe Nanoparticle Chains
Presence of Frster resonance energy transfer (FRET) between QDs in the chain.
Red shift of 36 nm
J. Phys. Chem. B. 2004,108,6927.
Nanochains of CdTe QDs formed from
individual particles through dipole -
dipole interaction
-
8/14/2019 GENERAL SEMINAR 2009.pptx
40/45
Gas sensors
Absorption of H2 led to the expansionof the crystalline lattice of Pd.
Gap between Pd NPs in an array
decreased, leading to higher electron
transfer.
On venting the H2, a reversible affect
was observed.
Hydrogen Sensors and Switches from
Electrodeposited Palladium nanowire Arrays
Science, 2001,293, 2227
Sensors for biomolecules
-
8/14/2019 GENERAL SEMINAR 2009.pptx
41/45
George Thomas and co workers, J. Am. Chem. Soc. 2005,127,6516.
Selective Detection of Cysteine and Glutathione Using Gold Nanorods
1 D A bl f P id F i li d A NP A A h T d M I S i
-
8/14/2019 GENERAL SEMINAR 2009.pptx
42/45
1-D Assembly of Peptide-Functionalized Au NPs: An Approach Toward Mercury Ion Sensing
Mandal, T. K. and co workers, J. Phys. Chem. C. 2007,111,1248.
Detection limit4 ppm
Future Perspectives
-
8/14/2019 GENERAL SEMINAR 2009.pptx
43/45
p
Development of preparation methods for large-scale production as well as
precise positioning of 1D NP arrays.
Better understanding of the formation mechanism of template-free NP
chains.
Control of interparticle distances in NP chains, so that distance-dependent
photonic and electronic transfer along the NP chains could be realized.
Production of NP chains consisting of multiple components, for example,
1D hybrid chains of metal and semiconductor NPs.
Conclusions
-
8/14/2019 GENERAL SEMINAR 2009.pptx
44/45
Controlled organisation of nanoparticles is an essential step for the
fabrication of nanomaterial based devices.
One dimensional organisation of NPs can be achieved either by template
assisted synthesis or by self assembly method.
The collective properties of 1D NP assemblies are evidently different from
single NPs.
1 D NP assemblies can be used as sensors for gases, bimolecules and toxic
metal ions.
There are plenty of unknown phenomena awaiting exploration and there are
also many problems requiring resolution.
-
8/14/2019 GENERAL SEMINAR 2009.pptx
45/45