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Chemistry and Nanomaterials
Carl C. WamserPortland State University
Nanomaterials Course - June 27, 2006
Nanoscale = billionths (10-9)
6 billion people8000 mile diameter
10 billion components8 inch diameter
Effects of Nanoscale
Structural differences:
Bulk CarbonNanoscale Carbon
Carbon Nanotubes Sumio Iijima - 1991
C60 (Buckeyball)Smalley, Curl, Kroto
1996 Nobel Prize
Graphite Diamond
Instrumentation / Imaging
• “Quantum Corral”
• 48 Fe atoms positioned by the STM used to image them
http://www.nano.gov/html/facts/home_facts.html
Dimensional Issues
nm µm mm m
Chemistry
Biology
Electronics
molecules polymers supramolecularassemblies
aminoacids
proteins cells/ tissues organisms
semi-conductors
transistors integratedcircuits
computers
ONAMIlength scale:
Chemistry Issues
• Structure / Dynamics / Synthesis
• Structure-Function Correlations
• Self-Assembled Systems
• Applications:– Materials– Biological– Environmental
Organic LEDs
Structure-Function Correlations (emission wavelengths)
Quantum Effects
Fluorescence of cadmium selenide nanoparticles
4 nm 2 nm
• Band gap depends on particle size(number of atoms in the particle)
Chemical Bonding
• Forces used to assemble structure:– Ionic– Metallic– Covalent– H-bonding– Metal-ligand– Van der Waals– π-π stacking
Ionic Bonding
• Molecular beaker epitaxy
• Layer-by-layer growth of polyelectrolytes
• Tom MalloukPenn State U
http://www.mapr.ucl.ac.be/~jonas/Home_page_AJ/Research/ESA/ESA.html
Ionic / Electrostatic Effects
• A molecular elevator
• Responsive to acid/base
• J. D. Badjic, et al., Accts. Chem. Res., in press.
• J.F. Stoddart, UCLA
Ionic / Electrostatic Effects
• Conformational Molecular Rectifiers, A. Troisi and M. A. Ratner, Nano Lett., 4(4), 591-595 (2004).
Metallic Bonding
melting point: 1337 °K
melting point: 650 °K
Gold Statue Gold nanoparticles
Nanoscale gold has different properties than bulk gold, including: appearance, solubility, and melting point.
thiol stabilized gold nanoparticle
gold nanoparticles (2 nm) in solutionJim Hutchison, U. Oregonhttp://darkwing.uoregon.edu/~hutchlab
Covalent Bonding - Carbon
Single-walled
carbon nanotubes:• armchair - metallic• zigzag - semiconducting• chiral - semiconducting
• multi-walled - metallic
Covalent Bonding - Carbon
Carbon nanotubes coated with diamond nanocrystals
M. L. Terranova, et al., Chem. Mater., 17(12) pp 3214 - 3220
Hydrogen Bonding
DNADouble Helix
http://www.haveland.com/ graphics/dna-3d.jpg
π-π Stacking - Liquid Crystals
Charge-Trapping Memory Device
Liu, C-Y.; Bard, A.J.; Acc. Chem. Res.
(1999), 32, 235-234.
Self-Assembled Monolayer
• Monolayer of DDB on graphite
(didodecylbenzene)
http://www.nanoscience.com/education/gallery/DDB_ani.htm
10 nm
Van der Waals Interactions
• SAMMSSelf-Assembled Monolayers on Mesoporous Supports
Glen Fryxell, PNNL
QuickTime™ and aTIFF (LZW) decompressor
are needed to see this picture.
http://samms.pnl.gov/
Polyporphyrin Interfacial Film (thin)
Polyporphyrin Interfacial Film (thick)
Photosynthetic Reaction Center
http://www.mpibp-frankfurt.mpg.de/~michael.hutter/rcenter.html
( 1988 Nobel Prize )( 1988 Nobel Prize )
Resources
• Nanochemistry references and websites:
Handbook of Nanotechnology, B. Bhushan, ed. (2004) Molecular Nanotechnology, D. E. Newton, ed. (2002) Integrated Chemical Systems, A. J. Bard (1994) Engines of Creation, K. Eric Drexler (1986)
( http://www.foresight.org/EOC/ ) “There’s Plenty of Room at the Bottom”, Richard Feynman (1959)
( http://www.zyvex.com/nanotech/feynman.html )
National Nanotechnology Initiative ( http://www.nano.gov/ ) Nano Letters - ACS Journal ( http://pubs.acs.org/journals/nalefd/ ) Materials Today - British journal ( http://www.materialstoday.com )