Construction of ZnCoP/CdLa2S4 Schottky Heterojunctions for Enhancing Photocatalytic Hydrogen Evolution

Photocatalytic hydrogen evolution by heterojunction photocatalysts is considered an effective way to address environmental and energy crises. In this work, a novel ZnCoP/CdLa 2 S 4 Schottky heterojunction was prepared via a physical mixing method assisted by water bath heating and used to enhance the efficiency of photocatalytic hydrogen production . Owing to the higher work function and metallic conductivity of ZnCoP , the photoinduced electrons can transfer from CdLa 2 S 4 to ZnCoP through the ZnCoP/CdLa 2 S 4 interface, which suppresses the recombination of photoinduced electrons and holes. Moreover, the Schottky heterojunction formed at the interface between ZnCoP and CdLa 2 S 4 inhibits electron backflow from ZnCoP to CdLa 2 S 4 , which further promotes the separation of electron-hole pairs. Meanwhile, the ZnCoP/CdLa 2 S 4 heterojunction exhibited enhanced visible light absorption compared to CdLa 2 S 4 . In addition, ZnCoP acts as an electron acceptor and hydrogen evolution active site. The synergistic effect of the tight ZnCoP/CdLa 2 S 4 interface, the higher work function and metallic conductivity of ZnCoP, and the formation of Schottky junctions significantly enhance the photocatalytic hydrogen production evolution performance of CdLa 2 S 4 . When the amount of ZnCoP was 30 wt% (wt%, mass fraction), the 30ZCP/CLS composite showed the highest photocatalytic performance, and the hydrogen production rate reached 10.26 mmol·g −1 ·h −1 under visible light irradiation and with Na 2 S and Na 2 SO 3 as sacrificial agents, which was 7.7 times that of CdLa 2 S 4 . Combined with the activity data and characterization results, a potential mechanism for photocatalytic hydrogen production over ZnCoP/CdLa 2 S 4 Schottky heterojunctions was proposed. In this work, a novel ZnCoP/CdLa 2 S 4 Schottky heterojunction was prepared for enhancing the photocatalytic hydrogen evolution performance.