Ab initio investigation on hybrid graphite-like structure made up of silicene and boron nitride

In this work, we report our results on the geometric and electronic properties of hybrid graphite-like structure made up of silicene and boron nitride (BN) layers. We predict from our calculations that this hybrid bulk system, with alternate layers of honeycomb silicene and BN, possesses physical properties similar to those of bulk graphite. We observe that there exists a weak van der Waals interaction between the layers of this hybrid system in contrast to the strong inter-layer covalent bonds present in multi-layers of silicene. Furthermore, our results for the electronic band structure and the density of states show that it is a semi-metal and the dispersion around the Fermi level (EF) is parabolic in nature and thus the charge carriers in this system behave as nearly-free-particle-like. These results indicate that the electronic properties of the hybrid bulk system resemble closely those of bulk graphite. Around EF the electronic band structures have contributions only from silicene layers and the BN layer acts only as a buffer layer in this hybrid system since it does not contribute to the electronic properties near EF. In case of bi-layers of silicene with a single BN layer kept in-between, we observe a linear dispersion around EF similar to that of graphene. However, the characteristic linear dispersion becomes parabola-like when the system is subjected to a compression along the transverse direction. Our present calculations show that the hybrid system based on silicon and BN can be a possible candidate for two-dimensional layered system, akin to graphite and multi-layers of graphene.