High energy region formation with increased electron density located on the MoS2 layer within MoS2/Gr heterostructure induced by C60 decoration

Abstract

MoS2/graphene (MoS2/Gr) heterostructure shows great potential in various applications due to its unique and complementary chemical and physical properties. However, high resistances of contact interfaces between the MoS2 and graphene lead to low performance of such heterostructure-based electronic devices. Doping strategy with C60 physically adsorbed on the surface of MoS2/Gr was explored theoretically here for the aim to tune the electron injection barrier of the MoS2/Gr. Calculated results indicate that the energy levels of the frontier orbitals of MoS2 and the Fermi level of graphene can be modulated effectively due to the increased interfacial interaction energy by doping with C60, which leads to a reduced electron injection barrier (by about 0.2 eV) from the Fermi level of graphene to the conduction band minimum of the MoS2. Therefore, it is predicted that C60 is an effective dopant to decrease the electron injection barrier and promote the photogenerated electron-hole separation in the MoS2/Gr. More importantly, a high energy region with increased electron density located on the MoS2 within in heterostructure was formed by C60 doping strategy. Our results indicate that C60 doping is an effective strategy to improve the electronic properties of MoS2/Gr, and then optimize the performance of such heterogeneous nanocomposites-based devices.