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Nano-Technology. Lee Zi Jing 3i3 (13). What is nano-technology?. Nano-technology is the study of matter at an atomic scale It generally deals with materials from 1 to 100 nano meters in size Nano-technology involves a diverse range of research.
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Nano-Technology Lee Zi Jing 3i3 (13)
What is nano-technology? • Nano-technology is the study of matter at an atomic scale • It generally deals with materials from 1 to 100 nano meters in size • Nano-technology involves a diverse range of research. • In this presentation, we will be examining the uses of nano carbon.
10-9 10-6 10-3 100 103 106 109 The nano scale • One nanometer (nm) is one billionth, or 10−9, of a meter. • A nanometer to a meter is marble to the size of the earth. • In the time a man takes to raise the razor the shave his beard, it has grown by a nano meter!
Carbon • Melting point: ~ 3500oC • Atomic radius: 0.077 nm • Basis in all organic componds • 10 mill. carbon componds
Bonding of Carbon Graphite Diamond
Nano carbon - Materials • Fullerene • Tubes • Cones • Carbon black • Horns • Rods • Foams • Nanodiamonds
~1 nm Fullerene • A fullerene is any molecule composed entirely of carbon, in the form of a hollow sphere, ellipsoid or tube. ”The most symmetrical large molecule” • Discovered in 1985 - Nobel prize Chemistry 1996, Curl, Kroto, and Smalley • C60, 70, 76 and 84.
Fullerene Properties • Symmetric shape → lubricant • Large surface area → catalyst • High temperature (~500oC) • High pressure • Hollow → caging particles
Fullerene Properties • Chemically stable as graphite - most reactive at pentagons • Crystal by weak van der Waals force • Superconductivity - K3C60: 19.2 K - RbCs2C60: 33 K
Discovered 1991, Iijima Roll-up vector: Tubes
Tube Properties • Carbon nanotubes are very flexible
Cones • Discovered 1994 (closed form) Ge & Sattler • 1997 (open form) Ebbesen et al. • Closed: same shape as HIV capsid • Possible scale-up production (open form) • Used for hydrogen storage Nano carbon cones at various angles of opening 19.2 o 38.9 o 60.0 o 84.6 o 112.9 o Scale : 200 nm
Carbon Black • Large industry • - millions of tons per year • Tires, black pigments, plastics, dry-cell batteries, UV-protection etc. • Size: 10 – 400 nm
Applications of nano carbon materials • Writing • Transistor • Antenna • Flat Screen Displays • Yarn
Writing C60 (Fullerene): 1000x better resolution than ink (Xerox) Carbon – graphite
Vacuum tubes - Nobel prize 1906, Thomson. Transistor Emitter Collector Base
Dipole, used for raiowaves Antennas Radio wave: ~ 3/4 m • Nanotube, used for optical waves Optical wave: L
Flat screen displays • Field emission
Yarn • MWCNT • Operational -196oC < T < 450oC • Electrical conducting • Toughness comparable to Kevlar • No rapture in knot
Nanocarbon - fullerene - ”most symmetrical” - tubes - ”strongest” - cones - ”one of the sharpest” - carbon black - ”large production” Properties - electrical, mechanical, thermal, storage, caging Applications - antenna, writing, transistor, yarn, flat screen displays Conclusion THANK YOU!