Effect of SILAR-anchored ZnFe_2O_4 on the BiVO_4 nanostructure: An attempt towards enhancing photoelectrochemical water splitting

摘要

Development of high performance photoanodes for application in solar-driven photoelectrochemical cells is considered a grand challenge. Various structures and materials have been studied to overcome the current performance limit of the photoanode in photoelectrochemical cells; however, the enhancement in both stability and photocurrent has not been realized to date. In our study, the successive ionic layer adsorption and reaction method is used to coat ZnFe2O4 nanoparticles on the BiVO4 photoanodes. Various characterizations about structural, morphological, and optical characterizations confirm the presence of anchored ZnFe2O4 nanoparticles over BiVO4. Showing remarkable stability, the photocurrent density of optimized BiVO4/ZnFe2O4 is significantly increased compared with that of the bare BiVO4 nanostructured thin film. Mott-Schottky and electrochemical impedance spectroscopy analyses demonstrate that the appropriate number of the successive ionic layer adsorption and reaction cycles leads to efficient charge transfer. Furthermore, the correlation among structural, morphological and optical properties is discussed here.