Electronic properties of MoS2/Be2C van der Waals heterostructure: Effect of Bi-axil strain and vertical electric field

Abstract

In this paper, the structural and electronic properties of MoS 2 /Be 2 C heterostructure and their dependence on the biaxial strain and external electric field were investigated by first-principle calculations. The band alignment of the MoS 2 /Be 2 C heterostructure is type II. As the tensile strain is increase to 4%, the band gap of MoS 2 /Be 2 C heterostructure decreases from 0.28 to 0.19 eV. At the same time, an indirect to direct band gap transition occurs. With further increasing the tensile strain, a type II to type III transition occurs for tensile strain larger than 6%. Compressive strain induced a transition from type II to type III band alignment. The MoS 2 /Be 2 C heterostructure can remain the type II band alignment, but the band gap decreases and increases for the positive and negative electric field applied. Thus, the electronic properties of MoS 2 /Be 2 C vdW heterostructures can by tuned by the biaxial strain and external electric field. • The structural and electronic properties of MoS 2 /Be 2 C heterostructure were investigated by first-principle calculations. • As the tensile strain increases to 4%, an indirect to direct band gap transition occurs. • This heterostructure remains a type II band alignment, but the band gap decreases with increasing the electric field.