Constructing SrTiO3-T/CdZnS heterostructure with tunable oxygen vacancies for solar-light-driven photocatalytic hydrogen evolution

Heterostructure plays significant roles in many photocatalytic reactions, as it can provide more efficient route for the charge carrier separation and transferring. Herein, we report a rational design of a new kind of photocatalyst, in which SrTiO3-T/Cd0.5Zn0.5S heterostructure is prepared via a simple hydrothermal method. SrTiO3 with oxygen vacancy is prepared by a controllable solid-state reaction of NaBH4 and SrTiO3 nanocrystals. The oxygen vacancies on the surface of SrTiO3 can be used as electron traps to attract electrons from Cd0.5Zn0.5S and provide proton reduction sites for H-2 production during the photocatalysis processing, thereby effectively inhibit the recombination of electron-hole pairs. It has demonstrated that SrTiO3-T/Cd0.5Zn0.5S nanocomposites can achieve the highest photocatalytic hydrogen evolution rate of 25.01 mmol g 1 h(-1) under visible light, which is about 2 times than that of the original Cd0.5Zn0.5S.