Fluorographane: a promising material for bipolar doping of MoS2

Abstract

Using first principles calculations we investigate the structural and electronic properties of interfaces between fluorographane and MoS₂. Unsymmetrical functionalization of graphene with H and F results in an intrinsic dipole moment perpendicular to the plane of the buckled graphene skeleton. Depending on the orientation of this dipole moment, the electronic properties of a physically absorbed MoS₂ monolayer can be switched from n- to p-type or vice versa. We show that one can realize vanishing n-type/p-type Schottky barrier heights when contacting MoS₂ to fluorographane. By applying a perpendicular electric field, the size of the Schottky barrier and the degree of doping can be tuned. Our calculations indicate that a fluorographane monolayer is a promising candidate for bipolar doping of MoS₂, which is vital in the design of novel technological applications based on two-dimensional materials.