Investigation of the structural and electronic properties of pristine and Au-embedded MoS_2/C60 and WSe_2/C60 van der Waals heterostructures: A first-principles study

摘要

The interaction of C60 molecule with pristine and Au-decorated MoS2 and WSe2 nanosheets were investigated using the density functional theory calculations. The results suggest that adsorption of C60 molecule on the surface of Au-embedded MoS2 is more energetically favorable than that on the pristine MoS2 sheet. Thus, Au-embedded MoS2 systems can interact with C60 molecule more strongly. The interaction of C60 molecule with WSe2 nanosheet was also found to be an energy favorable adsorption process. The large overlaps between the projected density of states of the carbon and Ag/Au atoms indicate the covalent nature of the interaction between them, manifested by the newly formed chemical bonds at the interface. This formation of covalent bonds was also revealed by the charge density difference plots of the considered systems. There is some charge accumulation between the newly formed Au-C bonds, indicating the covalent characteristics of the interaction. Based on the band structure plots, we found that the Ag-embedded and Au-embedded MoS2/C60 heterostructures show metallic behavior, whereas the pristine heterostructure exhibit semiconductor characteristics.