WO3/Cd0.5Zn0.5S heterojunction for highly efficient visible-light photocatalytic H2 evolution

Abstract

The construction of heterogeneous structure is an effective measure to enhance photocatalytic hydrogen evolution. Herein, the WO3/Cd0.5Zn0.5S (WO3/CZS) heterogeneous catalyst is prepared via a simple hydrothermal method. The two-dimensional WO3 nanosheet is prepared by roasting the precipitates of sodium tungstate and hydrochloric acid. WO3 can effectively increase the absorption intensity of visible light, thereby generate more photogenerated carriers. Meanwhile, based on the universality of two-dimensional materials, the addition of WO3 nanosheet improves the stability of WO3/CZS composite catalyst. Additionally, the tight heterogeneous interface between WO3 and CZS ensures efficient electrons transport, which inhibits the recombination of electron-hole pairs. The optimized 30%-WO3/Cd0.5Zn0.5S photocatalyst shows the highest H2 production rate of 42.26 mmol g−1 h−1 under visible light, which is 3.43 times higher than the pure Cd0.5Zn0.5S photocatalyst (12.31 mmol g−1 h−1).