Construction and Mechanism Study of Z-scheme BiVO4/ WO3 Photoelectrodes Based on Anodized Tungsten Oxide Foils

Tungsten trioxide is an ideal candidate for photoelectrodes because of its good visible light response, oxidizing ability, and photocorrosion resistance. However, the defects of tungsten trioxide, including poor photogenerated charge separation efficiency, reducing ability, and active site density, limit its wide application. In this paper, BiVO4/WO3 was in situ grown on tungsten foi by anodic oxidation combined with electrodeposition-chemical oxidation methods. Under the synergic effect of simulated solar irradiation and auxiliary bias voltage of 0. 6 V, the degradation rates of tetracycline hydrochloride, oxytetracycline and chlortetracycline by the BiVO4/WO3 photoelectrodes were 95. 8%, 85. 6%, and 96. 9%, respectively. In addition, the photocatalytic fuel cell constructed with a BiVO4/WO3 photoelectrode as anode and a platinumcarbon cathode exhibited excellent power production performance. When methanol was used as the fuel, the filling factor FF could reach 0. 3793, which is 1. 35 times that of WO3 photoelectrode. The interface between BiVO4 and WO3 forms a Z-scheme heterojunction, which endows the BiVO4/WO3 photoelectrode has the advantages of multiple active sites, strong light capture, high photogenerated charge separation efficiency and redox capacity.