Effects of different amounts of N heteroatoms on the structural and electronic properties of graphene and the adsorption behavior of Li atoms

This paper investigates the effects of different amounts of N heteroatoms on the structural and electronic properties of pristine graphene and the adsorption behavior of Li atoms on N-doped graphene via first-principles calculations. The obtained results suggest that new N hexagonal structures are formed around the C hexagonal structure. The third-nearest neighbor structures are always maintained between the new N atoms and one of the original ones. Among the different N-doped graphene samples, the di- and tetra-N-doped and superlattice C3N exhibit semiconductor properties, while the others exhibit non-magnetic metallic properties. Studies on superlattice C3N reveal that N-doped graphene does not exhibit the aggregation of Li adatoms typical of pristine graphene. Single Li and two Li adatoms show non-magnetic metallic properties and semiconductor properties, respectively. The formation of multiple N-doped graphene samples explains the physical formation process of superlattice C3N. Their corresponding electronic properties and Li adsorption behavior are expected to motivate graphene applications in gas storage and sensing, catalysts, and biological devices.