Comparative photoelectrochemical characteristics of heterostructure and composite based on BiVO₄ and WO₃

Films of heterostructure BiVO₄/WO₃, composite BiVO₄ with WO₃ and pure BiVO₄ were obtained by electrochemical deposition. Analysis of photoelectrochemical characteristics of such films showed that observed increase in photocurrent quantum yield and decrease in overvoltage of oxygen evolution on the photoanode in row from pure BiVO₄ films, than in heterostructure BiVO4/WO₃, after that—composite BiVO₄–WO₃. The reason of such positive effect of reducing the energy losses associated with the surface recombination of electrons and holes and reduction of losses at the stage of interfacial charge transfer in the BiVO₄–WO₃ composite compared with the heterostructure BiVO₄/WO₃ and pure BiVO₄.