Surface Reconstruction and Passivation of BiVO 4 Photoanodes Depending on the "Structure Breaker" Cs

• Published in: JACS Au 2023-07, Vol.3 (7), p.1851-1863
• Main Authors: Tao, Chen, Jiang, Yi, Ding, Yunxuan, Jia, Bingquan, Liu, Ruitong, Li, Peifeng, Yang, Wenxing, Xia, Lixin, Sun, Licheng, Zhang, Biaobiao
• Format: Article
• Language: English
• ISSN: 2691-3704; 2691-3704
• DOI: 10.1021/jacsau.3c00100

Monoclinic BiVO is one of the most promising photoanode materials for solar water splitting. The photoelectrochemical performance of a BiVO photoanode could be significantly influenced by the noncovalent interactions of redox-inert metal cations at the photoanode-electrolyte interfaces, but this point has not been well investigated. In this work, we studied the Cs -dependent surface reconstruction and passivation of BiVO photoanodes. Owing to the "structure breaker" nature of Cs , the Cs at the BiVO photoanode-electrolyte interfaces participated in BiVO surface photocorrosion to form a Cs -doped bismuth vanadium oxide amorphous thin layer, which inhibited the continuous photocorrosion of BiVO and promoted surface charge transfer and water oxidation. The resulting cocatalyst-free BiVO photoanodes achieved 3.3 mA cm photocurrent for water oxidation. With the modification of FeOOH catalysts, the photocurrent at 1.23 V reached 5.1 mA cm , and a steady photocurrent of 3.0 mA cm at 0.8 V was maintained for 30 h. This work provides new insights into the understanding of Cs chemistry and the effects of redox-inert cations at the electrode-electrolyte interfaces.