Tailored BiVO 4 Photoanode Hydrophobic Microenvironment Enables Water Oxidative H 2 O 2 Accumulation

作者：Man Ou, Mei Geng, Xiangle Fang, Wenfan Shao, Fenghong Bai, Shipeng Wan, Caichao Ye, Yuping Wu, Yuhui Chen · 发表于：Advanced Science · 年份：2023 · DOI：10.1002/advs.202300169 · 被引用次数：41 · 研究领域：Advanced Photocatalysis Techniques、Copper-based nanomaterials and applications、Electrocatalysts for Energy Conversion

Abstract Direct photoelectrochemical 2‐electron water oxidation to renewable H 2 O 2 production on an anode increases the value of solar water splitting. BiVO 4 has a theoretical thermodynamic activity trend toward highly selective water oxidation H 2 O 2 formation, but the challenges of competing 4‐electron O 2 evolution and H 2 O 2 decomposition reaction need to overcome. The influence of surface microenvironment has never been considered as a possible activity loss factor in the BiVO 4 ‐based system. Herein, it is theoretically and experimentally demonstrated that the situ confined O 2 , where coating BiVO 4 with hydrophobic polymers, can regulate the thermodynamic activity aiming for water oxidation H 2 O 2 . Also, the hydrophobicity is responsible for the H 2 O 2 production and decomposition process kinetically. Therefore, after the addition of hydrophobic polytetrafluoroethylene on BiVO 4 surface, it achieves an average Faradaic efficiency (FE) of 81.6% in a wide applied bias region (0.6–2.1 V vs RHE) with the best FE of 85%, which is 4‐time higher than BiVO 4 photoanode. The accumulated H 2 O 2 concentration can reach 150 µ m at 1.23 V versus RHE under AM 1.5 illumination in 2 h. This concept of modifying the catalyst surface microenvironment via stable polymers provides a new approach to tune the multiple‐electrons competitive reactions in aqueous solution.