Tailoring Carrier Dynamics of BiVO4 Photoanode via Dual Incorporation of Au and Co(OH)x Cooperative Modification for Photoelectrochemical Water Splitting

Abstract Photoelectrochemical solar to hydrogen production is a promising way to achieve carbon neutrality, but severe charge recombination in photoanodes limits the conversion efficiency. Herein, Au nanoparticles and Co(OH) x co‐sensitized bismuth vanadate (BiVO 4 ) to construct AuCo(OH) x /BiVO 4 photoanode for significantly enhancing the performance of photoelectrochemical water splitting. This process significantly improves the bulk charge carrier separation efficiency, the surface kinetics of water oxidation, and the electron density of BiVO 4 photoanode through Au surface plasmon resonance (SPR) and Co(OH) x oxygen evolution catalysts effect. Additionally, the enhancement of the *O and the *OOH generation accelerate the oxygen evolution reaction kinetics. Consequently, the constructed AuCo(OH) x /BiVO 4 photoanode demonstrates an excellent photocurrent of 6.2 mA cm −2 at 1.23 V versus reversible hydrogen electrode and a stable continuous output within 42 h. This work contributes to developing high‐efficiency and high‐stability photoanodes for solar H 2 production through SPR effect and oxygen evolution catalysts.