Fabrication of BiVO4 photoanode catalyzed with bimetallic sulfide nanoparticles for enhanced photoelectrochemical water oxidation

Abstract

The photoelectrochemical water oxidation ability of BiVO4 is usually restrained by its low separation efficiency of the photogenerated charge and slow kinetics for water oxidation. Here, FeCoS2 bimetallic sulfide nanoparticles are successfully coated on BiVO4 photoanode to address these problems. The photocurrent density of FeCoS2/BiVO4 photoanode is 3.08 times that of BiVO4 photoanode. Furthermore, the charge separation efficiency can reach 75% and the charge injection efficiency reaches nearly 78%. The onset potential of FeCoS2/BiVO4 shifts 300 mV negatively, while the incident photon-to-electron conversion efficiency value of FeCoS2/BiVO4 is 2.86 folds of BiVO4. The enhancement benefits from the loading of FeCoS2, which promotes the separation of photogenerated electron and hole, and inhibits the recombination of photogenerated charge and hole.