Fabrication of CdS/Ni-MOF bifunctional catalyst for the photocatalytic hydrogen evolution coupled with benzyl alcohol’s oxidation

In this study, the CdS/Ni-MOF74 (CNM) photocatalyst was synthesized via the combination of CdS with the advantageous properties of MOFs. The composites exhibit a wide visible absorption and photo electron-hole separation efficiency, thus giving improved bifunctional properties for H 2 evolution in conjunction with the benzyl alcohol’s oxidation. The results indicate that as synthesized CNM3 catalyst shows excellent efficiency of hydrogen evolution having an evolution rate of 5783 µmol g −1 h −1 , and the amount of benzaldehyde generated after benzyl alcohol’s oxidation reached 8059.8 µmol g −1 . After four cycles, the H 2 evolution efficiency remained at 5351 µmol g −1 h −1 . According to experiments using radical trapping and mechanistic investigations, it was revealed that the photogenerated holes (h + ) were the key species mainly responsible for benzaldehyde production as well as H 2 evolution. This research work could lead to new approaches resulting in simultaneous organic oxidation processes and hydrogen evolution by using MOF-derived hybrid photocatalysts.