Carbon nanotubes(CNTs) are tiny carbon tubes with a diameter of just over one nanometer (nm).
Carbon nanotubes are long, thin tubes of carbon atoms with hexagonal graphene rolled up into a tube up to several centimeters long. Each carbon atom is honeycombed to three other carbon atoms. The cylindrical CNT tubes have unique electronic and thermal properties. By design, they exist with a cylindrical wall as single-walled nanotubes (SWNTs) and also as multi-walled nanotubes (MWNTs) multi-walled carbon nanotubes in the form of cylinder-in-cylinder.
Since graphene behaves like semiconductors, CNT tubes can be used as semiconductors for transistors. In addition, carbon nanotubes are used as electrode material in double- layer capacitors and in Nano Emissive Displays (NED).