Carbon content and layers number controlling electronic properties of hybridized graphene and boron nitride

Using the first-principles density functional theory calculation, the most stable structure of hybridized hexagonal boron nitride and graphene domains (h-BNC) was studied, and the influence of carbon atomic ratio and layers number on band gap was investigated. The energy calculation shows that the more h-BN and graphene concentrate in h-BNC, the more stable structure will be. The calculation of band gap shows that band gap of single-layer h-BNC decrease with increasing of carbon atomic ratio. When graphene is in h-BN, the band gap decreases in a rough law; however, when h-BN is in graphene, there is only a general trend of band gap decreasing. In addition, we found that as the number of h-BNC layers increases, the band gap "collapse". Therefore, the band gap of h-BNC can be adjusted by controlling the carbon content and the number of layers synergistically. The reason for the large drop of the band gap is charge transfer between the h-BNC layers. This research proves the rationality of the structure of h-BNC appearing in previous experiments, and has a referring role in adjusting h-BNC band gap to an appropriate value in the process. It is significant for application of h-BNC in band gap engineering.