Solar water oxidation using TaON–BiVO4 photoanodes functionalized with WO3

Abstract

Efficient solar-powered water oxidation over BiVO₄-based anodes requires coupling photoactive semiconductors to improve inferior activity and stability. Herein, we examine how functionalization with coated tungsten trioxide WO₃ affects the photoelectrocatalytic performance of TaON–BiVO₄ photoanodes prepared by the doctor-blade method. The effects of the formation of the particularly-porous microstructure and PEC performance of the resulting anodes are explored. Significant enhancements were achieved in water oxidation photocurrent densities at 1.23 V (vs. RHE) with the use of TaON–BiVO₄/WO₃ photoanodes compared to unmodified TaON–BiVO₄. All the composites and photoanodes were studied via numerous characterization methods. Besides, the formation process and probable transfer mechanism of photoinduced carriers were also investigated in detail.