A novel Z-scheme WO₃/CdWO₄ photocatalyst with enhanced visible-light photocatalytic activity for the degradation of organic pollutants

A novel Z-scheme WO₃/CdWO₄ photocatalyst has been fabricated with sheet-like tungsten trioxide (WO₃) hybridized by rod-like cadmium tungstate (CdWO₄) via a hydrothermal and chemisorption method. The as-synthesized WO₃/CdWO₄ photocatalyst exhibited enhanced photocatalytic efficiency for the degradation of different organic dyes under visible light irradiation. It was found that the photocatalytic performance of the composite WO₃/CdWO₄ was much higher than that of either WO₃ or CdWO₄ for the degradation of each organic dye. The highest activity of the composite was recorded for the degradation of MB which was about 7 times greater than pure CdWO₄ and 2.3 times that of pure WO₃. The enhanced performance of the photocatalyst was mainly attributed to the increased surface area and introduction of WO₃ into the composite sample, which can induce higher adsorption activity for organic dyes and increased electron-hole separation at the interface between two semiconductors by establishing an inner electric field.