Electric Field and Strain Effect on Graphene-MoS2 Hybrid Structure: Ab Initio Calculations

The electronic structures of graphene-MoS2 heterojunction under tension and external electric field were examined on the basis of density-functional theory. The tension of MoS2 changes the hybrid structure from semiconductor to metal. The transition is from the sensitive dependence of the bandgap of MoS2 on the lattice constant. The vertical electric field has little influence on the bandgap of MoS2., while it can also adjust the charge transfer between monolayer MoS2 and graphene. In addition, the Schottky barrier is linearly dependent on the electric field intensity with an effective vacuum spacing of 1.3 angstrom. It is also discussed in detail that the bandgap of MoS2 dependence on the lattice constant and the S-S spacing.