Visible-Light-Driven Photocatalytic H2 Production from H2O Boosted by Hydroxyl Groups on Alumina

Alumina is widely used in thermocatalysis in both scientific research and industry, but has limited application in photocatalysis due to its poor abilities in light absorption and charge transfer. Herein, we apply an alumina with an appropriate content of OH groups (AOH) to support CdS and Pt nanoparticles to form a CdS/Pt/AOH photocatalyst for the visible-light-driven photocatalytic H-2 production from H2O. The H-2 evolution rate on CdS/Pt/AOH (2524.99 mu mol h(-1)) is 9.59 and 1.60 times higher than those on Pt/CdS (263.23 mu mol h(-1)) and photocatalyst prepared by loading CdS and Pt nanoparticles on the widely used gamma-Al2O3 (CdS/Pt/AO, 1576.84 mu mol h(-1)), respectively. Moreover, CdS/Pt/AOH exhibits an apparent quantum efficiency of 46.3%, which is 1.86 times higher than that on CdS/Pt/AO (24.9%). The OH groups on AOH improve the separation of photogenerated electron-hole pairs, and promote the removal of the O atoms produced from H2O splitting to release more catalytic active sites for H-2 formation and to suppress the recombination of H and O atoms. This is responsible for the enhanced visible-light-driven photocatalytic H-2 production from H2O on CdS/Pt/AOH. These results open up a new way to achieve more efficient visible-light-driven photocatalysis.

Automated summary

Alumina, when combined with an appropriate content of OH groups (AOH), can effectively enhance the visible-light-driven photocatalytic H-2 production from H2O by supporting CdS and Pt nanoparticles. The OH groups improve the separation of photogenerated electron-hole pairs and promote the removal of O atoms, resulting in higher H-2 evolution rate and quantum efficiency.