C-doped ZnS-ZnO/Rh nanosheets as multijunctioned photocatalysts for effective H2 generation from pure water under solar simulating light

A combined solvothermal method and post-annealing to synthesize highly active ZnS-ZnO nanosheets is presented. ZnO was produced on ZnS nanosheets by thermal annealing ZnS/ethylenediamine in air. From combined studies of experimental and computational works, we revealed that during annealing, carbon (C) element was a major dopant from the decomposition of ethylenediamine, which was unintentionally doped into the ZnS-ZnO, and gave major impacts on enhanced visible-light photocatalysis. Rhodium (Rh) was deposited by in situ photoreduction to form a ZnS-ZnO/Rh catalyst composite. This multijunctioned photocatalyst was outstanding for H-2 generation from pure water under solar simulating light due to effective charge separation by Z-scheme heterojunction of ZnS and ZnO and Schottky junction of Rh-cocatalysts/semiconductors. This facile method realizes multijunctioned ZnS-ZnO/Rh photocatalysts with substantial defects that are very promising for solar energy harvesting applications.

Automated summary

A highly active ZnS-ZnO nanosheets were synthesized using a combined solvothermal method and post-annealing, with intentional or unintentional doping of elements such as carbon and rhodium to enhance visible-light photocatalysis. The multijunctioned photocatalyst showed outstanding performance for hydrogen generation from pure water under solar simulating light due to effective charge separation by Z-scheme heterojunction of ZnS and ZnO and Schottky junction of Rh-cocatalysts/semiconductors.