Preparation and Photoelectrochemical Performance of BiVO4/CuBi(2)O(4)Thin Film Photoanodes

The poor separation and significant recombination of electron-hole pairs and slow transfer mobility ofcharge carriers limit the performance of BiVO4for photoelectrochemical???PEC???water splitting.Herein???we presentthe ternary metal oxide deposition of p-type CuBi2O4as a route to obtain a novel photocatalyst layer on BiVO4to formn-BiVO4/p-CuBi2O4a novel composite photoanode for PEC water splitting.It is found that BiVO4/CuBi2O4andBiVO4/CuBi2O4/Co-Pi thin films addition show better PEC performance compared with bare BiVO4under visible illu???mination.At1.23V???vs.RHE???potential???BiVO4/CuBi2O4thin film show excellent PEC water oxidation performance???and the photocurrent density reaches2.8mA/cm2.The photocurrent density of BiVO4/CuBi2O4/Co-Pi thin film loadedwith cobalt-phosphate???Co-Pi???reaches4.45mA/cm2.The curront densities are3.1times and4.9times of bare BiVO4???respectively.BiVO4and CuBi2O4construct a p-n heterojunction to boost its poor electron-hole separation and trans???port properties using the built-in electrical potential.The X-ray diffraction???XRD??????UV-Vis measurements???electro-chemical impedance spectroscopy???EIS???and schematic diagram of band structure absorption spectra reveal the en???hanced PEC performance and light stability of the prepared electrode materials???when it is applied to PEC water split???ting.Based on the study???we have gained an in-depth understanding of the BiVO4/CuBi2O4and BiVO4/CuBi2O4/Co-Pi composite as high potential in efficient PEC water splitting devices.