Modulation of electronic and magnetic properties of graphene-triangular h-BN hybrid through monovacancy: Carbon vacancy-BN size coupling

Abstract

The effects of monovacancy on the stability, electronic and magnetic properties of the triangular h-BN embedded graphene nanosheet (G) were investigated by density functional theory (DFT) method. The interface is the energetically most favorable site for creating a vacancy in the GBN nanosheet. Defective GBN hybrids are either metallic or exhibit a small band gap energy ranging from 0.01 to 0.23 eV. The dangling bonds induced a localized magnetic moment ranging from 0.02 to 3 μB in the defective hybrid. The magnetic moment induced by the carbon vacancy in the G layout of the N-rich hybrid interestingly increases with island size. This coupling effect can be explained by the local charge imbalance between charge centers of opposite sign. We could not observe similar behavior in B- rich hybrids. Our results showed that the narrow bandgap and induced magnetic moment of the vacancy-defected GBN hybrid could be easily modulated and thus could be potential materials for spintronic /electronic applications.