http://gened.emc.maricopa.edu/bio/BIO181/BIOBK/BioBookCELL2.html

1
Science Imitates Life
Lily Parenchyma Cell (cross-section) (TEM x7,210)
Liver Cell (TEM x9,400)
http//gened.emc.maricopa.edu/bio/BIO181/BIOBK/Bio
BookCELL2.html
2
Quantum Dots
http//web.mit.edu/chemistry/nanocluster/home.html
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Nanotechnology Nano-gears
http//nanozine.com/nanogear.htm
4
Nanoscale Metallic Particles

• Chemical and Physical Properties
• intermediate between the bulk metal and
  molecular clusters
• properties effected by large fraction of
  surface atoms
• morphology
• electronic structure (quantum confinement)

Scheme adapted from Schmid, G. In Clusters and
Colloids Schmid, G., Ed. VCH, Weinheim,1994.
5
Surface Area
Scheme adapted from Schmid, G. In Clusters and
Colloids Schmid, G., Ed. VCH, Weinheim,1994.
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Heterogeneous Catalysis

• High surface area supports
• Maximize metal surface area
• Bimetallic improve selectivity and activity
• Electronic and structural modifiers

Scheme adapted from http//www.chem.northwestern.
edu/brochure/stair.html
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Supported Metal Nanoparticles

• Direct Methanol Fuel Cell (DMFC)
• methanol electroxidation
• rapid degradation of anode catalyst
• performance
• current state-of-the-art catalyst
• supported Pt, Pt-alloys (Pt-Ru)

http//www.methanol.org/images/schema_fuel.jpg
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Cyclic Voltammetry
Sample cyclic voltammograms of a Pt electrode (3
mm) a) 0.5 M H2SO4 b) 0.5 M H2SO4 4 M CH3OH.
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Size Effects in Nanoscale Materials
Ionization Potential as a function of particle
size.
Adapted from Jena, P Khanna, S.N. Rao, B.K.
Physics and Chemistry of Finite Systems From
Clusters to Crystals (NATO-ASI Series). 1992
(Deventer Kluwer). Woltersdorf, J. Nepijko,
A.S. Pippel, E. Surf. Sci. 1968, 12, 134.