Nitrogen Dopants in Carbon Nanomaterials: Defects or a New Opportunity?

Substitutional N-doping of carbon nanomaterials refers to the chemical functionalization method that replaces a part of the carbon atoms in fullerene, carbon nanotubes, or graphene by nitrogen. N-doping has attracted a tremendous amount of research attention for their unique possibilities, spanning from its ability to engineer various physiochemical properties of carbon nanomaterials in a stable manner with different dopant configurations. Many viable configurations of N-dopants are accompanied by typical structural defects, while still preserving the structural symmetry in the basal graphitic plane. Here, the physicochemical features are highlighted and the exciting challenges of N-dopants in carbon nanomaterials identified, with particular emphasis on the broad tunability of the material properties and relevant emerging applications.