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 H2 production from H2O. The H2 evolution rate on CdS/Pt/AOH (2524.99 μmol h–1) is 9.59 and 1.60 times higher than those on Pt/CdS (263.23 μmol h–1) and photocatalyst prepared by loading CdS and Pt nanoparticles on the widely used γ-Al2O3 (CdS/Pt/AO, 1576.84 μmol 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 H2 formation and to suppress the recombination of H and O atoms. This is responsible for the enhanced visible-light-driven photocatalytic H2 production from H2O on CdS/Pt/AOH. These results open up a new way to achieve more efficient visible-light-driven photocatalysis.