Nanotube FAQ:
I'm going to try and make this stuff simple, but of course I will add in references and links to papers for the more science-inclined of you out there. If anyone has further questions or revisions, send something my way.
To get things started:
If you do not know what nanotubes are, you have been out of the loop for some time. If you do not pay attention to science news, then do not feel bad because nanotechnology has only been around since the early 90s. The field has not taken off until now because of new technology that allows us to study, characterize, and manipulate things on the nano scale.
What is nanotechnology?
Nanotechnology is the study anything that is nano-sized. That is about 0.00000001 cm long, and I would wager all those zeros to be about a 1.5cm long, so a nanometer is about a 100 millionth the size of the decimal as it appears on this screen.
What are carbon nanotubes?
Carbon nanotubes (CNTs) are a new form of carbon (other forms are graphite, diamond and Bucky Balls) where a sheet of graphite (a network solid) rolled into a tube. Nanotubes look like rolled up chicken wire (the carbon is arranged in hexagons). On average, the tubes are 2 nm in diameter and at least 100 nm in length. The longest nanotube made so far was a few milimeters long. CNTs are made using a number of techniques such as Laser Ablation or High Pressure CO (HiPCO). Both of these methods use metal catalysts such as iron to speed the reaction.
Why study CNTs?
In general, CNTs and nanotechnology represent a new field of science. Nanoscale objects behave differently then we might expect the macro scale equivalent to behave. The new field of science has been created to discover these differences, quantify them, etc. Today's nanotechnology research hopes to pave the way to create a host of applications that range from tiny machies that repair the human body to computer chips that are too small for the eye to see.
In particular, nanotubes have numerous properties that we have not begun to understand. Here are a few exampes:
- The carbon-carbon bond in nanotubes is one of the strongest covalent bonds. Its strength-to-weight ratio is extremely better than steel or other metals. Some applications include super-strong cables that we could use to build a space elevator.
- Depending on how the tubes are "rolled" (armchair, zigzag, and chiral configurations), the conductivity will change. The conductivity of an armchair nanotube is like that of a metal. Basically, this means nanotubes are wires and scientists can use them to make mini circuits.
- Nanotubes are resistent to the environment inside the human body. If scientists could figure out how to put chemicals inside the nanotubes, the CNTs could act like little capsules. These bio-transport systems would bring drugs to specific targets inside the body and would cut down on the amount of drugs we need to take and the severity of their side-effects.