Interface Engineering of Bismuth Vanadate Through Mo,Tb Co-Doping and Fe₂TiO₅ Integration for Enhanced Solar Water Oxidation

A synergistic strategy integrating bulk electronic modulation via Mo/Tb co-doping with surface catalytic enhancement via Fe₂TiO₅ coupling is developed to overcome the intrinsic limitations of BiVO₄ photoanodes for photoelectrochemical water splitting. The Mo/Tb‑BVO:Fe₂TiO₅ photoanode achieves a high photocurrent density of 4.91 mA cm⁻² at 1.23 V vs. RHE, representing a 2.6‑fold enhancement over pristine BiVO₄. To explore the kinetic characteristics and clarify the mechanism that accounts for the enhanced PEC performance, a combined method encompassing scanning photoelectrochemical microscopy, intensity-modulated photocurrent spectroscopy, and an oxygen evolution reaction model was adopted. By implementing multiple modification strategies, this study overcomes intrinsic limitations in carrier separation, migration, and utilization. The results highlight that metal co-doping and cocatalyst loading are indispensable for rational photoanode construction and high-efficiency solar water splitting.