Effects of electric field and strain on the Schottky barrier of the bilayer van der Waals heterostructures of graphene and pure/hydrogenated PC3 monolayer

Abstract The carbon-based van der Waals (vdW) heterostructures with metal-semiconductor (M-S) junction have shown great potential for nanodevices and optoelectronic applications; however, the Schottky barrier at interface restricts the injection efficiency of charges. Here, we systematically investigate the effect of the electronic field and biaxial strain on the electronic properties and the Schottky barrier height (SBH) of the PC3/graphene(G) and PC3H/G vdW heterostructures through first-principles calculations. The results show that the charge redistribution at interface leads to a shift of the Fermi level, which determines the contact type and height of the Schottky barrier. Moreover, the contact type could be tuned from p-type Schottky contact to Ohmic contact by electronic field or in-plane biaxial strain, thus obtaining highly efficient charge transfer. Most importantly, we demonstrate that hydrogenation of PC3 is an effective strategy to partly screen the external electronic field, whereas more sensitive to strain for inducing the contact type transform and SBH variation of the PC3H/G heterostructure. This work provides a promising to design novel carbon-based nonmetal vdW heterostructures and explore their potential applications in electronic and optoelectronic devices.