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.