Functionalization Approaches,Mechanisms and Surface Features of Functionalized Carbon Nanotubes

Two approaches for surface modification of carbon nanotubes(CNT) are covalent functionalization and non-covalent functionalization.The mechanism of covalent approach is to attach the reactive groups to the surface of CNT by oxidative or reduced reactions firstly,then transforming the groups to organic moieties,or to polymeric chains by grafting from or click reactions.The mechanism of non-covalent functionalization of carbon nanotubes involves the ?-? interactions between ?-system of carbon nanotubes and ?-containing organic moieties or polymers and adsorption of surfactants on surface of carbon nanotubes.The surface features of functionalized carbon nanotubes suggested by Kim et al.can be expressed as the surface containing reactive groups is the 1st generation(1G),the attachment of organic moieties on CNT is 2G and the surface linked with polymeric chains is 3G.