Density functional theory based study of the structural and electronic properties of graphitic heterostructures

Abstract

With the trend of miniaturization and maximizing the potential of nanomaterials, the properties of important materials in electronic devices such as graphene and silicene have been widely investigated. This presentation aims to provide computational information for the achievement of this goal by studying the structural stability and electronic properties of hexagonal-boron nitride on graphene (h-BN/G) hetero-bilayer and silicene on hexagonal-boron nitride on graphene (Si/h-BN/G) heterostructure using density functional theory. The calculations were performed through the Vienna Ab Initio Simulation Package (VASP) implemented with three different approximations namely, LDA, GGA, and GGA with Tkatchenko-Scheffler van der Waals (vdW) correction. From the calculations, the h-BN/G hetero-bilayer and Si/h-BN/G heterostructures were found to be computationally stable relative to the experimental binding energy and interlayer distance between graphitic layers. Moreover, it was observed that layers of graphitic structures interact through the Van der Waals forces (vdW), thus calculations of such structures must be done with vdW corrections. Lastly, the application of perpendicular strain modified the band gap and Dirac cone shifting of the system.  These characteristics suggested that the hetero-bilayer and heterostructure have great potential for electronic device applications.