Modulating the doping state of transition metal ions in ZnS for enhanced photocatalytic activity

Transition metal ions (M = Ag+, Cu2+, Co2+, and Cr3+) are surface or homogeneously doped into ZnS via facile cation-exchange reaction, and while Ag+ and Cu2+ doping does not induce sulphur vacancies (Vs) or zinc vacancies (VZn), Co2+ and Cr3+ doping induces Vs. The surface doped catalysts exhibit greatly higher activity than the ZnS and homogenous doped catalysts for H2 evolution and CO2 reduction. The important role of the doping state on affecting the photo-absorption, carrier separation efficiency, and photoreaction kinetics has been systemically investigated and proposed. This work sheds light on the future design and fabrication of high-performance photocatalysts by element doping. The transition metal ion surface doped ZnS catalysts exhibit greatly higher activity than homogeneous doped catalysts. The role of doping states in activity enhancement has been systemically investigated.

Automated summary

Transition metal ion surface doping greatly enhances the activity of ZnS catalysts for H2 evolution and CO2 reduction, with the doping state playing a crucial role in affecting their photo-absorption and reaction kinetics. This research provides insights for the future design and fabrication of high-performance photocatalysts.