Band-Gap Engineering of Graphene Heterostructures by Substitutional Doping with B₃ N₃

We investigated the energetics and electronic structure of B₃ N₃ -doped graphene employing density functional theory calculations with the generalized gradient approximation. Our calculations reveal that all of the B₃ N₃ -doped graphene structures are semiconducting, irrespective of the periodicity of the B₃ N₃ embedded into the graphene network. This is in contrast to graphene nanomeshes, which are either semiconductors or metals depending on the mesh arrangement. In B₃ N₃ -doped graphene, the effective masses for both electrons and holes are small. The band gap in the B₃ N₃ -doped graphene networks and the total energy of the B₃ N₃ -doped graphene are inversely proportional to the B₃ N₃ spacing. Furthermore, both properties depend on whether or not the graphene region possesses a Clar structure. In particular, the sheets with a Clar structure exhibit a wider band gap and a slightly lower total energy than those without a Clar structure.