Density functional theory study of graphene adhesion on WX2 (X = S and Se) monolayer: Role of atom vacancy and atomic reorganization defects

Abstract

AbstractDefects usually play an important role in the modification of the properties of materials. In this investigation, atom vacancy and atomic reorganization defects in various heterostructures obtained using different pristine (or defect‐free) and defective transition metal dichalcogenides (TMDCs) with pristine and defective graphene have been studied using density functional theory (DFT) calculation. Results reveal that: (i) the contact of pristine and defective graphene with various pristine and defective TMDCs is energetically stable, (ii) the stability of these heterostructures driven by dispersion interaction, (iii) the presence of defect significantly influences the work function of the resulting heterostructure, (iv) the pristine graphene/pristine TMDCs heterostructures are metallic in nature with large Schottky barrier (ΦSBH), (v) the heterostructures involving defective graphene are direct band gap semiconductors, (vi) the heterostructures involving defective WS2 are also direct band gap semiconductors, and (vii) the SW defective graphene with pristine WS2/WSe2 forms type‐II heterojunction.