Fe2TiO5 as an Efficient Co-catalyst To Improve the Photoelectrochemical Water Splitting Performance of BiVO4

Fe₂TiO₅ was synthesized via the solvothermal method and adopted as co-catalyst to improve the photoelectrochemical (PEC) water splitting performance of BiVO₄ photoanode. After surface modification by Fe₂TiO₅, the BiVO₄/Fe₂TiO₅ photoanode shows a 300 mV cathodic shift in onset potential and 3 times enhancement in photocurrent, which delivers a photocurrent density of 3.2 mA/cm² at 1.23 V vs reverse hydrogen electrode. Systematic optical, electrochemical, and intensity-modulated photocurrent spectroscopy characterizations were performed to explore the role of Fe₂TiO₅ and reveal that the enhanced PEC performance is mainly caused by the surface passivation effect of Fe₂TiO₅.