Dual modification of BiVO photoanode for synergistically boosting photoelectrochemical water splitting.

Bismuth vanadate (BiVO) is a promising nanomaterial for photoelectrochemical (PEC) water oxidation. However, the serious charge recombination and sluggish water oxidation kinetics limit its performance. Herein, an integrated photoanode was successfully constructed by modifying BiVO (BV) with InO (In) layer and further decorating amorphous FeNi hydroxides (FeNi). The BV/In/FeNi photoanode exhibited a remarkable photocurrent density of 4.0 mA cm at 1.23 V, which is approximately 3.6 times larger than that of pure BV. And the water oxidation reaction kinetics has an over 200% increased. This improvement was mainly because the formation of BV/In heterojunction inhibited charge recombination, and the decoration of cocatalyst FeNi facilitated the water oxidation reaction kinetics and accelerated hole transfer to electrolyte. Our work provides another possible route to develop high-efficiency photoanodes for practical applications in solar conversion.