1 Chapter 10: Nanostructures and Solids with Low-Dimensional Properties Nanoscience: the study of phenomena and manipulation of materials at atomic, molecular, and macromolecular scales, where properties differ significantly from those at larger scale. Nanotechnology: the production and application of structures, devices, and systems for controlling shape and size at the nanometer scale.
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Nanostructures and Solids with Low-Dimensional Propertiesmichael.lufaso/chem4627/ch10_solid_state.pdf1 Chapter 10: Nanostructures and Solids with Low-Dimensional Properties Nanoscience:
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Chapter 10: Nanostructures and Solids with
Low-Dimensional Properties
Nanoscience: the study of phenomena and manipulation of materials at atomic, molecular, and macromolecular scales, where properties differ significantly from those at larger scale.
Nanotechnology: the production and application of structures, devices, and systems for controlling shape and size at the nanometer scale.
Larger nanoparticles have featureless absorptions resemble bulk solid
Nanogold
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Optical properties
Zinc oxide
Magnetic properties
Solid Dc (nm)Fe 14Co 70Ni 55Fe3O4 55
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Physical Properties:
Melting Point
macroscale nanoscaleMajority of atoms are: almost all inside the
objectsplit between the inside and the surface
Changing an object’s size:
has minimal effect on the % of atoms on the surface
has a substantial effect on the % of atoms on the surface
The melting point: doesn’t depend on size
is lower for smaller particles
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Fabrication Methods
Self Assembly by Crystal Growth
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Graphite
Intercalation Compounds of Graphite
KC8
CaC8
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chevroletvoltage.com
“Each Volt’s battery cell contains a carbon anode (the negative electrode), a manganese-based cathode (the positive electrode) and a safety reinforced separator, which provides the medium for the transfer of electrical charge ions between the anode and the cathode inside the battery cell.”
Buckminster Fullerene
K3C60
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Armchair nanotubes are metallic. Zig-zag and chiral nanotubes can be either metallic or semiconducting.
zig-zag armchair chiral
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Arc-discharge
Laser Furnace
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•Hydrocarbon vapor passed through a tube furnace. •SWNTs or MWNTs depends on size and temperature of catalyst (Fe, Ni with NH3). •Low-temperature (600-900°C) yields MWNTs, higher temperature (900-1200°C) favors SWNTs.
Chemical vapor deposition
Carbon Nanotube Growth
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Problems with CNT production•Mixture of metallic and semiconducting •Alignment and positioning
A breakthrough?•ST-cut single crystal quartz substrates •ethanol/methanol as carbon source •Cu nanoparticles as catalysts
Results•1.55 to 1.78 nm diameter SWNT •95% semiconducting •CNT aligned
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Teflon Coated CNT Forest
Spinning Carbon Nanotubes
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Space Elevator
Space Elevator Cable
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Photolithography
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Polyacetylene
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Conducting polymers: Repeating units
Bonding in Polyacetylene
E
Peierls’ Theorem
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Metal
Conjugated polymer
Glass
ITO
Organic Polymer LED
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Gao, F. G.; Bard, A. J. J. Am. Chem. Soc. 2000, 122, 7426.