Van der Waals heterostructure of graphene and As2S3: Tuning the Schottky barrier height by vertical strain

Graphene-based van der Waals (vdW) heterojunction has attracted increasing attention in the field of optoelectronics, nanoelectronics, and spintronics. The tunability of Schottky barrier height (SBH) formed in such kind of heterojunction is rather of significance for practical applications. In this study, based on first-principles calculations, we have systematically investigated the electronic structures and interfacial characteristics of graphene/As2S3 heterojunction. The results show the intrinsic electronic properties of the corresponding individual counterparts are preserved after contacting. The Bader charge analysis indicates the transferred amounts of electrons from As2S3 to graphene increasing with the decrease of interlayer distance. Consequently, the Schottky contact will be tuned from n-type into p-type once the interlayer distance is lower than 2.78 angstrom. Our findings imply that the SBH is controllable, which is highly desirable in the nano-electronic devices.