Tunable electronic and magnetic properties in B_xN_yC_z nanohybrids: effect of domain segregation

Abstract

Motivated by recent experimental realization of the hybrid nanostructures of graphene and hexagonal boron nitride (h-BN) sheet, we have investigated the modification in the electronic structure as well as structural and magnetic properties of two-dimensional sheets with B_xN_y and graphitic C_z nanodomains, with various shapes and sizes using ab initio density functional theory. We find that embedding of domain-segregated B_xN_y or C_z nanodomains of different shapes and sizes in graphene or h-BN sheet platform, respectively, is energetically less costly and thermodynamically favorable to synthesize under suitable experimental conditions. Among the various nanodomains, the hexagonal-shaped B_xN_y and Cz nanodomains patched with graphene and h-BN sheet, respectively, are found to be stabler compared to others. Moreover, both the shape and size of the embedded B_xN_y (C_z) nanodomains have significant effects in regulating the graphene (h-BN sheet) electronic structure. Interestingly, we find that the presence of triangular-shaped B_xN_y nanodomain in graphene results in tunable semiconducting, metallic, and half-metallic electronic state depending on nanodomain geometries and its concentrations. Our study clearly shows a variety of electronic states, suggesting potential routes for band-gap engineering of these hybrid B_xN_yC_z nanomaterials for advanced device applications.