dynamics of excited states in nanoscale materials brian m. tissue department of chemistry virginia...
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Dynamics of Excited States in Nanoscale Materials
Brian M. Tissue
Department of ChemistryVirginia Polytechnic Institute and State UniversityBlacksburg, VA [email protected]
Outline
History and terminology Materials preparation Materials characterization Dynamics Summary
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Fire Opal
E. Fritsch et al., The nanostructure of fire opal, J. Non-Cryst. Solids, 352 (2006) 3957.
Chip Clark, http://www.mnh.si.edu/
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Natural Nanostructures
Manuka (scarab) beetle Morpho Butterfly
Andrew R. Parker & Helen E. Townley, Biomimetics of photonic nanostructures, Nature Nanotechnology 2 (2007) 347. 4
Antireflective Moth Eyes
http://www.asknature.org/
Reflexite display Optics product data sheethttp://www.physorg.com/news122899685.html; C.-H. Sun, P. Jiang, and B. Jiang, Broadband moth-eye antireflection coatings on silicon, Appl. Phys. Lett. 92 (2008) 061112 5
Copyright Trustees of the British Museum, http://www.britishmuseum.org.
The Lycurgus Cup
Reflected light Transmitted light
Late Roman, 4th century AD(colloidal gold and silver)
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Michael Faraday 1857
http://aveburybooks.com/faraday/catalog.htmlM. Faraday, The Bakerian Lecture: Experimental Relations of Gold (and Other Metals) to Light,, Phil. Trans. R. Soc. Lond., 147 (1857) 145.
...mere variation in the size of its particles gave rise to a variety of resultant colours.
The state of division of these particles must be extreme; they have not as yet been seen by any power of the microscope.
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Monolayer Films
Benjamin Franklin (1771) dropped ‘not more than a Tea Spoonful’ of oil onto Clapham Pond
Lord Rayleigh (1890) calculated film thickness to be 1.6 nm
Agnes Pockels, Surface Tension, Nature 43 (1891) 437.
1930s Langmuir-Blodgett films 1940 Katharine Blodgett anti-reflective glass
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Working Definition of Nanoscale
fine particles: 100 to 2500 nm nanomaterials: one or more dimensions between
1 and 100 nm ultrafine particles, nanoparticles, nanocrystals,
quantum dots (semiconductors) nanocubes, nanosheets, nanoplates, nanowires,
nanoflowers, etc. nanorods (solid), single-walled and multi-walled
nanotubes (hollow) clusters: few to hundreds of atoms
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http://cobweb.ecn.purdue.edu/~janes/whats_nano.htm 10
Nanoscale Descriptors
by medium: colloids, aerosols, hydrosols by number of phases: nanocomposite by construction: nanoarrays, nanostructures
(often on surface) aspect ratio: length-to-width size distribution:
< ±10 %: monodispersed > ±10 %: polydispersed
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L.B. Kiss et al., The real origin of lognormal size distributions of nanoparticles in vapor growth processes, Nanostruct. Mater. 12 (1999) 327-332.
Nanocomposites/Nanostructureshttp://www.nrc-cnrc.gc.ca/eng/news/nrc/2003/07/03/nanocomposites.html
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T. C. Chong et al., Laser precision engineering: from microfabrication to nanoprocessing, Laser & Photon. Rev. 4 (2010) 123.
Nanoparticles are Composites
Andrew Maynard, NIOSH and Yasuo Ito, Argonne National Lab, NSF Workshop Report on “Emerging Issues in Nanoparticle Aerosol Science and Technology (NAST)” University of California, Los Angeles, June 27-28, 2003.
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Materials Preparation
Bottom-up (chemical) easier to scale up
Top-down (physical) precise control of
dimensions and proximity
Hybrid (scaffolding)
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Bottom Up
gas-phase inert-gas
condensation spray pyrolysis pulsed-laser
deposition
condensed-phase homogeneous
precipitation seed-mediated
growth self-assembly
(micellar) sol-gel glass-ceramic
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Controlling Nucleation and Growth
NSF Workshop Report on “Emerging Issues in Nanoparticle Aerosol Science and Technology (NAST)” University of California, Los Angeles, June 27-28, 2003. 16
Top Down
lithography block copolymer
patterning optical interference electron beam
(scribing)
contact embossing/molding pattern transfer dip pen lithography
17M. Volatier et al., Extremely high aspect ratio GaAs and GaAs/AlGaAs nanowaveguides fabricated using chlorine ICP etching with N2-promoted passivation, Nanotech. 21 (2010) 134014.
Light Well: ATunable Free-Electron Light Source on a Chip
related to Smith–Purcell effect
G. Adamo et al., Phys. Rev. Lett. 103 (2009) 113901. 18
Materials Characterization
Small angle X-ray scattering
Electron microscopy
Scanning probe microscopy
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I review for J. Lumin.
X-ray Scattering at APS
grazing-incidence small-angle X-ray scattering (GISAXS)
ultrasmall-angle X-ray scattering (USAXS)
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Z. Jiang et al., Capturing the Crystalline Phase of Two-Dimensional Nanocrystal Superlattices in Action, Nano Lett. 10 (2010) 799–803.
F. Zhang, et al., Quantitative Measurement of Nanoparticle Halo Formation around Colloidal Microspheres in Binary Mixtures, Langmuir 24 (2008) 6504-6508.
2 nm
Imaging Methods
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Veeco Instruments, Application Note AN48.
1−103 500−10810−106
HRTEM: Defects in BN Sheet
O.L. Krivanek et al., Atom-by-atom structural and chemical analysis by annular dark-field electron microscopy, Nature 464 (2010) 571.
red: borongreen: nitrogenyellow: carbonblue: oxygen
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HRTEM: Citrate-capped gold n.p.
Z. Lee et al., Direct Imaging of Soft-Hard Interfaces Enabled by Graphene, Nano Lett. 9 (2009) 3365.
2 nm
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SEM Cathodoluminescence (1)
24X. Zhou et al., The Origin of Green Emission of ZnO Microcrystallites: Surface-Dependent Light Emission Studied by Cathodoluminescence, J. Phys. Chem. C 111 (2007) 12091.
SEM Cathodoluminescence (2)
25H. Xue, Probing the strain effect on near band edge emission of a curved ZnO nanowire via spatially resolved cathodoluminescence, Nanotech. 21 (2010) 215701.
Scanning Probe Microscopy(STM, AFM, etc)
26Veeco Instruments, Application Note AN48.
Chemical Force Microscopy
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Y. Sugimoto et al., Chemical identification of individual surface atoms by atomic force microscopy, Nature 446 (2007) 64.
Near-Field Scanning Optical Microscopy (NSOM)
28F. de Lange et al., Cell biology beyond the diffraction limit: near-field scanning optical microscopy, J. Cell Sci. 114 (2001) 4153.
L. Zhou et al., Direct near-field optical imaging of UV bowtie nanoantennas, Optics Express 17 (2009) 20301.
Dynamics
Quantum dots and FRET
Localized emitter structural/proximity effects surroundings effects phonon spectrum changes
Plasmonics
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I review for J. Lumin. too!
Quantum Dot Absorbance
L. Brus, Chemical Approaches to Seminconductor Nanocrystals, J. Phys. Chem. Solids 59 (1998) 459.30
Quantum Dot Luminescence
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A.L. Rogach, Energy transfer with semiconductor nanocrystals, J. Mater. Chem. (2009) 1208-1221.
M. Jones, G.D. Scholes, On the use of time-resolved photoluminescence as a probe of nanocrystal photoexcitation dynamics, J. Mater. Chem. 20 (2010) 3533.
Fluorescence Resonant Energy Transfer (FRET) donor/acceptor
spectral overlap distance
dependence 1/d6
dipole-dipole orientation
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A.L. Rogach, Energy transfer with semiconductor nanocrystals, J. Mater. Chem. (2009) 1208-1221.
Quantum dot FRET
33A.L. Rogach, Energy transfer with semiconductor nanocrystals, J. Mater. Chem. (2009) 1208-1221.
Localized Emitter in a Nanocomposite
crystallinity and defect concentration
dopant concentration
metastable/disordered structure dopant concentration and distribution surface proximity surroundings effects size-dependent phonon effects
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12-nm fcc Ni; P.M. Derlet et al., Phys. Rev. Lett. 87 (2001) 205501.
Surroundings Effect (spontaneous transition rate)
7-nm Eu3+:Y2O3
dispersed in different media
Line assumes 0.23 filling factor
35R.S. Meltzer, Dependence of fluorescence lifetimes of Y2O3:Eu3+ nanoparticles on the surrounding medium, Phys. Rev. B 60 (1999) R14012.
Size Effects on Nonradiative Rates
dopant segregation proximity to defects/surface electron-phonon interaction phonon density of states (PDOS)
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Energy Flow in a Nanocomposite
J. Yang et al., Mesoporous Silica Encapsulating Upconversion Luminescence Rare-Earth Fluoride Nanorods for Secondary Excitation, Langmuir 26 (2010) 8850.
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Size-Dependent PDOS
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G. Liu, X. Chen, Spectroscopic properties of lanthanides in nanomaterials, in Handbook on the Physics and Chemistry of Rare Earths, vol. 37, K.A. Gschneidner, Jr., J.-C.G. Bünzli, V.K. Pecharsky, Eds., (2007).
Plasmonics
39X. Huang, S. Neretina, M.A. El-Sayed, Gold Nanorods: From Synthesis and Properties to Biological and Biomedical Applications, Adv. Mater. 21 (2009) 4880.
Plasmonics
“A glance through the recent literature reveals a substantial interest in the physics of minute metal particles.”
J. Appl. Phys., 47 (1976) 2200.40
M. Fleischmann, P.J. Hendra A.J. McQuillan, Raman spectra of pyridine adsorbed at a silver electrode, Chem. Phys. Lett. 26 (1974) 163-166.
Nano Lett. 10(3) 2010
Composite Au Nanostructures
for Fluorescence Studies in Visible Light Nanoassembled Plasmonic-Photonic Hybrid Cavity for Tailored
Light-Matter Coupling Two-Dimensional Quasistatic Stationary Short Range Surface
Plasmons in Flat Nanoprisms Drude Relaxation Rate in Grained Gold Nanoantennas LSPR Study of the Kinetics of the Liquid−Solid Phase Transition in
Sn Nanoparticles Trapping and Sensing 10 nm Metal Nanoparticles Using Plasmonic
Dipole Antennas
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Energy Transfer Distance Dependence
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M. Malicki, et al., Excited-state dynamics and dye–dye interactions in dye-coated gold nanoparticles with varying alkyl spacer lengths, Phys. Chem. Chem. Phys., 12 (2010) 6267.
Size Dependence
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J. Zhang, Y. Fu, J.R. Lakowicz, Luminescent Silica Core/Silver Shell Encapsulated with Eu(III) Complex, J. Phys. Chem. C 113 (2009) 19404.
Fluorophore Engineering
44Y. Fu, J.R. Lakowicz, Enhanced Single-Molecule Detection using Porous Silver Membrane, J. Phys. Chem. C 114 (2010) 7492.
Single Molecule Spectroscopy
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S. Kuhn, U. Hakanson, L. Rogobete, and V. Sandoghdar, Enhancement of Single-Molecule Fluorescence Using a Gold Nanoparticle as an Optical Nanoantenna, Phys. Rev. Lett. 97 (2006) 017402.
Summary
The Future
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Future
More precise control over size, proximity, and complexity in nanostructures
<100 nm resolution in optical imaging methods 3-D nanoscale imaging Engineered excited-state
dynamics The unexpected
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C. L. Degen et al., Nanoscale magnetic resonance imaging, PNAS 106 (2009) 1313.
There's Plenty of Room at the Bottom:An Invitation to Enter a New Field of PhysicsRichard Feynman, 1959.
...possible (I think) for a physicist to synthesize any chemical substance that the chemist writes down. Give the orders and the physicist synthesizes it. How? Put the atoms down where the chemist says, and so you make the substance. The problems of chemistry and biology can be greatly helped if our ability to see what we are doing, and to do things on an atomic level, is ultimately developed–a development which I think cannot be avoided.
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Thanks!
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