Promotion of multi-electron transfer for enhanced photocatalysis: A review focused on oxygen reduction reaction

• Published in: Applied surface science Vol. 358; pp. 28 - 45
• Main Authors: Wang, Changhua, Zhang, Xintong, Liu, Yichun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.12.2015
• Subjects: Charge carriers; Hydroxyl radicals; Multi-electron; Oxygen reduction; Photocatalysis; Photocatalyst; Photocatalysts; Readers; Reduction; Semiconductor; Semiconductors; Separation; Oxygen reduction; Semiconductor; Multi-electron; Photocatalyst
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2015.08.055

•Oxygen reduction reaction (ORR) in photocatalysis process is focused.•Multi-electron transfer ORR is reviewed.•This review provides a guide to access to enhanced photocatalysis via multi-electron transfer. Semiconductor photocatalysis has attracted significant interest for solar light induced environmental remediation and solar fuel generation. As is well known, photocatalytic performance is determined by three steps: photoexcitation, separation and transport of photogenerated charge carriers, and surface reactions. To achieve higher efficiency, significant efforts have been made on improvement of efficiency of above first two steps, which have been well documented in recent review articles. In contrast, this review intends to focus on strategies moving onto the third step of improvement for enhanced photocatalysis wherein active oxygen species including superoxide radical, hydrogen peroxide, hydroxyl radical are in situ detected. Particularly, surface electron-transfer reduction of oxygen over single component photocatalysts is reviewed and systems enabling multi-electron transfer induced oxygen reduction reaction (ORR) are highlighted. It is expected this review could provide a guideline for readers to better understand the critical role of ORR over photocatalyst in charge carrier separation and transfer and obtain reliable results for enhanced aerobic photocatalysis.