Inserting MOF into flaky CdS photocatalyst forming special structure and active sites for efficient hydrogen production

Due to unique structure and properties of MOFs, a well-designed functional CdS/ZIF-67 composite photocatalyst was successfully synthesized by hydrothermal synthesis to achieve efficient hydrogen evolution. The obtained composite photocatalyst can not only make use of the specific surface area of ZIF-67 to provide a larger reaction place, but also can positively promote the reaction by binding sites between CdS and ZIF-67. Under visible light (5 W LED white light) irradiation, the maximum amount of hydrogen evolution reached 308 μmol in 5 h which was about 50 times higher than that of pure ZIF-67. The composite photocatalyst exhibited a significantly stronger stability than single component. The in-depth study of binding sites by electrochemical experiments showed that the photocurrent of the photocatalyst has increased to 1.8 μA cm−3, which showed that the existence of binding sites could effectively improve the electron transfer rate. And the synergy between them also can promote the separation of electron-holes and reduce the recombination rate. Therefore, reaction mechanism was proposed from the view of electron transfer for deep understanding.