Figure 1.

Carbon nanotubes (CNT). CNT are thin and long hollow fiber-like nanomaterials composed of a single, double or multiple layers of rolled graphene. The names are derived from the number of cyliders, known as single-walled carbon nanotubes (SWCNT), double-walled carbon nanotubes (DWCNT) or multi-walled carbon nanotubes (MWCNT). Surface modification by adding functional groups to the CNT surface (functionalization) is designed to change the surface properties and e.g. change CNT dispersion in the polar solvent (water). Presented is carboxylation and amine functionalization.