Carbon Nanotubes include Carbon-60 “Buckyball” (1 nm) and Rolled sheets of graphite (graphene). Three types of Carbon Nanotubes conformations are (i) armchair (top-to-bottom), (ii) zigzag (side-to-side) and (iii) chiral (corner-to-corner). Carbon Nanotubes are of Single and Multi-walled (SWNT, MWNT) types. Singlewalled nanotubes (SWNTs) have one shell of carbon atoms in a hexagonal arrangement, Multiwalled nanotubes (MWNTs) consist of multiple concentrically nested carbon tubes, similar to the rings of a tree trunk. Each type has its advantages and disadvantages. MWNTs are easier and less expensive to produce because current synthesis methods for SWNTs result in major concentrations of impurities that require removal by acid treatment. But MWNTs have a higher occurrence of structural defects, which diminishes their useful properties. Some companies prefer SWNTs because they do not have such defects and their properties are consequently stronger. MWNTs will likely become the material of choice for structural reinforcement, where low price matters more than high purity. Cell phone and notebook computer batteries use carbon nanotubes to last longer, to be more recyclable and give improved energy delivery.
Uses of Carbon Nanotubes are based on properties, these are:
Light-weight, high-strength materials - tennis rackets (“nanotube nylon”) - bullet-proof vests - space elevator.

Conductive materials - “quantum wires” - fuel cell application (using Pt electrode)Biosensors and Biomedical materials - soluble nanotubes (more applications)