Photocatalytic selective oxidation of aromatic alcohols coupled with hydrogen evolution over CdS/WO3 composites

Simultaneously utilizing photogenerated electrons and holes to convert renewable biomass and its derivatives into corresponding value-added products and hydrogen (H-2) is a promising strategy to deal with the energy and environmental crisis. Herein, we report a facile hydrothermal method to construct a direct Z-scheme CdS/WO3 binary composite for photocatalytic coupling redox reaction, simultaneously producing H-2 and selectively converting aromatic alcohols into aromatic aldehydes in one pot. Compared with bare CdS and WO3, the CdS/WO3 binary composite exhibits significantly enhanced performance for this photocatalytic coupled redox reaction, which is ascribed to the extended light harvesting range, efficient charge carrier separation rate and optimized redox capability of CdS/WO3 composite. Furthermore, the feasibility of converting various aromatic alcohols to corresponding aldehydes coupled with H-2 evolution on the CdS/WO3 photocatalyst is proved and a reasonable reaction mechanism is proposed. It is hoped that this work can provide a new insight into the construction of direct Z-scheme photocatalysts to effectively utilize the photogenerated electrons and holes for photocatalytic coupled redox reaction. (C) 2022, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

Simultaneously utilizing photogenerated electrons and holes to convert renewable biomass and its derivatives into value-added products and hydrogen (H-2) is a promising strategy. In this study, a facile hydrothermal method is used to construct a direct Z-scheme CdS/WO3 binary composite for photocatalytic coupled redox reaction, producing H-2 and selectively converting aromatic alcohols into aromatic aldehydes in one pot. The CdS/WO3 binary composite exhibits significantly enhanced performance compared to bare CdS and WO3, attributed to its extended light harvesting range, efficient charge carrier separation rate, and optimized redox capability. The feasibility of converting various aromatic alcohols to aldehydes coupled with H-2 evolution on the CdS/WO3 photocatalyst is demonstrated, along with a proposed reaction mechanism.