ZnO/MoX(2) (X = S, Se) composites used for visible light photocatalysis

Hybrid density functional has been adopted to investigate the structural, electronic, and optical properties of ZnO/MoS(2) and ZnO/MoSe(2) composites as compared with the results of ZnO, MoS(2), and MoSe(2) monolayers. The results indicate that MoS(2) and MoSe(2) monolayers could contact with monolayer ZnO to form ZnO/MoS(2) and ZnO/MoSe(2) heterostructures through van der Waals (vdW) interactions. The calculated bandgap of ZnO/MoS(2) (ZnO/MoSe(2)) is narrower than that of ZnO or MoS(2) (MoSe(2)) monolayers, facilitating the shift of light absorption edges of the composites towards visible light in comparison with bare ZnO and MoX(2) monolayers. Through the application of strain, the ZnO/MoS(2) and ZnO/MoSe(2) composites which own suitable bandgaps, band edge positions, efficient charge separation, and good visible light absorption will be promising for visible light photocatalytic water splitting. These results provide a route for design and development of efficient ZnO/MoS(2) and ZnO/MoSe(2) photocatalysts for water splitting.