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 C 3 N exhibit semiconductor properties, while the others exhibit non-magnetic metallic properties. Studies on superlattice C 3 N 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 C 3 N. Their corresponding electronic properties and Li adsorption behavior are expected to motivate graphene applications in gas storage and sensing, catalysts, and biological devices.