Transcript Carbon Nanotubes

Carbon Nanotubes
Ray Olang
What is it?
History
How are they made?
• Nanotube formation is allowed because their
formation eliminates high-energy dangling
bonds and increases strain energy and thus
decreasing total energy; the net decrease in
energy is what allows the formation of
nanotubes along with the addition of energy
for the overall reaction.
Yeah, how?
• The methods of creating nanotubes
are arc discharge, laser ablation, high
pressure carbon monoxide, and
chemical vapor deposition; most of
the methods take place in a vacuum
or with process gases.
So What?
• Can be metallic or semi-conducting depending on
orientation (special gate voltage controlled band gaps)
• Light, yet strong (more s-character)
– The Young's modulus of the best nanotubes can be as high as
1000 GPa (5x stiffer than steel)
– The tensile strength 63 Gpa (50x higher than steel)
• Own insulation (multi-walled)
– All nanotubes are expected to be very good thermal conductors along the
tube, but good insulators laterally to the tube axis.
– Concentric
• SMALL (3000K limit)
•
•
Defects lower conductivity
Current density x1000 Silver
Conclusion
• Their mechanical properties and unique
properties make them both interesting
as well as potentially useful in future
technologies.
waterproof tear-resistant cloth fibers, combat
jackets, high-tensile concrete, increasing
polymer elasticity, artificial muscles, chemical
nanowires, high-speed flywheels, buckypaper,
space elevator, filters, etc