An MIL-53(FeNiCo) decorated BiVO₄ photoanode for efficient photoelectrochemical water oxidation

BiVO₄ is considered as one of the important candidate materials for photoelectrochemical water splitting technology. However, the low efficiency of charge separation and poor kinetics of water oxidation limit its performance in PEC water splitting. In this work, a BiVO₄/MIL-53(FeNiCo) photoanode was constructed by a facile hydrothermal deposition method, exhibiting excellent water oxidation ability under AM 1.5 G light irradiation, and achieving a photocurrent density of 3.53 mA cm^-2 at 1.23 V_RHE, which is about 3.2 times that of pure BiVO₄. The electrochemical test results demonstrate that the decoration of MIL-53(FeNiCo) could enhance the charge transfer and accelerate the kinetics of water oxidation reaction, thus leading to excellent PEC water splitting performance. The PEC stability is also significantly improved, indicating that MIL-53(FeNiCo) allows BiVO₄ to be used for water oxidation for stable PEC water oxidation.