Electronic Properties of Nitrogen-Atom-Adsorbed Graphene Nanoribbons With Armchair Edges

Using first-principles calculations based on density functional theory, we systematically study adsorption of nitrogen atom on graphene nanoribbons with armchair edges (AGNRs). It is found that the N atom prefers to be adsorbed at the edge. The adsorption mechanism is discussed from the strong hybridization between the electron states in both N adatom and AGNR. It is also exhibited that the ??_p-d molecular bands appear in the electronic structures. For some AGNRs, the electronic structures are spin-polarized, in which the ??_p-d molecular bands are split off. However, other AGNRs are spin-unpolarized, which can be turned into p-type AGNRs. These results indicate that the properties of AGNRs can be strongly modified through the adsorption of N atom.