Bismuth vanadate single crystal particles modified with tungsten for efficient photoeletrochemical water oxidation

Abstract

Highly efficient water oxidation utilizing visible light is a crucial step in water splitting. Bismuth vanadate (BiVO4) single crystal particles have attracted much attention in water oxidation recently, owing to their outstanding physicochemical properties and exposed active facets. The performance of BiVO4 single crystal particles is generally hindered by their poor conductivity and worse charge separation. Doping BiVO4 single crystal particles with other metal elements has been considered as an efficient way to improve their conductivity, charge separation and performance. However, there are few successful reports, because structure and morphology of BiVO4 single crystal particles are easily changed by addition of impurities. Here, we present that W doped BiVO4 crystal particles were successfully achieved by developing a simple impregnation method following with a high temperature annealing process. The obtained W-BiVO4 single crystal particles exhibited improved conductivity, carrier density and thereby enhanced activity for water oxidation. The solar energy conversion of the W-BiVO4 electrode was doubled compared with the pristine one. Thus, this work opens an avenue for developing efficient single crystal particle photocatalysts.