Chapter 8 - Carbon nanotubes

Abstract

This chapter provides an introduction to carbon nanotubes. The single-walled carbon nanotubes (SWNTs) consist of singular graphene cylindrical walls with diameters ranging between 1 and 2 nm and multiwalled carbon nanotubes (MWNTs) have thicker walls, consisting of several coaxial graphene cylinders separated by a spacing (0.34 nm) that is close to the interlayer distance in graphite. The outer diameters of MWNTs range between 2 nm and 25 nm, and the inner hollows range from ∼1 nm to 8 nm. In MWNTs, there is no three-dimensional ordering between the individual graphite layers, suggesting that the interlayer structure is turbostratic. Individual SWNTs have uniform diameter, although when formed they show a strong tendency to pack together in larger bundles. In fact, the packing occurs in a regular triangular lattice structure with an intertube spacing in each of the bundles that corresponds to about 0.315 nm and a lattice parameter of 1.7 nm.