The Effects of Vacancy and External Electric Field on the Electronic Properties of the MoSi2N4/Graphene Heterostructure

Abstract

Abstract Recently, the newly synthesized septuple-atomic layer two-dimensional (2D) material MoSi2N4 (MSN) has attracted attention worldwide. Our work delves into the effects of vacancies and external electric fields on the electronic properties of the MSN/Graphene (Gr) heterostructure using the first-principles calculations. We find that four types of defective structures: N-in, N-out, Si and Mo vacancy defects of monolayer MSN and MSN/Gr heterostructure are stable in air. Moreover, vacancy defects can effectively modulate the charge transfer at the interface of the MSN/Gr heterostructure as well as the work function of the pristine monolayer MSN and MSN/Gr heterostructure. Finally, the application of an external electric field enables the dynamic switching between n-type and p-type Schottky contacts. Our work may offer the possibility of going beyond conventional Schottky diodes based on MSN/Gr heterostructures.