Energetics and electronic structures of N-doped graphene nanoribbons with pyridinic and graphitic edges

Abstract

Using the density functional theory, we study the energetics and electronic structures of graphene nanoribbons of which edges are substituted by N atoms. Our calculations showed that the edge N atoms with pyridinic structure mimic the π environment of C atoms, participating the π electron network of C atoms. In contrast, N atoms act as impurities for the π electron network of the nanoribbons when they are terminated by H atoms, leading to versatile edge localized state those are hardly synthesized using C and H atoms. The total energy of N-doped nanoribbons is the same as that of the pristine graphene nanoribbons, irrespective of the edge hydrogenation, and gradually decreases with increasing nanoribbon width. We also found that the edge hydrogenation decrease and increase the stability of the N-doped graphene nanoribbons with armchair and zigzag edges, respectively.