Boosting BiVO4 photoanode performance via organic–inorganic cocatalyst synergy for efficient water splitting

Abstract

Bismuth vanadate (BiVO₄) emerges as a promising photoanode material due to its suitable bandgap and excellent visible light absorption. However, the abundance of defect states on the BiVO₄ surface limits the enhancement of its photoelectrochemical water oxidation performance. To overcome these limitations, this study proposes loading 3,4-thienedicarboxylic acid (TDA) and nickel ferrite (NiFe₂O₄) onto BiVO₄, leveraging synergistic interactions between organic small molecules and inorganic materials to boost photoelectrochemical water oxidation reaction efficiency. The study demonstrates that the BiVO₄/TDA/NiFe₂O₄ photoanode, fabricated via immersion self-assembly and spin-coating, achieves a photocurrent density of 6.5 mA cm⁻² at 1.23 V vs. RHE-5.3 times higher than bare BiVO₄. This research provides new insights into enhancing photoelectrochemical performance by modifying BiVO₄ with small molecules.