A PW12/Bi2WO6 composite photocatalyst for enhanced visible light photocatalytic degradation of organic dye pollutants

A novel PW12/Bi2WO6 composite photocatalyst has been successfully prepared by a facile and effective approach, where PW12 denotes the Keggin-type polyoxometalate H3PW12O40, and the as-prepared photocatalyst was characterized by infrared spectroscopy (IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and photoelectrochemical measurements. The photocatalytic activity of the PW12/Bi2WO6 composite photocatalyst was evaluated by using a model reaction of the visible light photocatalytic degradation of rhodamine B (RhB). Under visible light, the PW12/Bi2WO6 photocatalyst exhibited a remarkable performance improvement in the photocatalytic degradation of RhB, as compared with pure Bi2WO6. The PW12/Bi2WO6 composite exhibited high photocatalytic activity with an RhB degradation ratio of >99% in 4 hours, which is almost 2 times as much as that of pure Bi2WO6. The action mechanism of the enhanced photocatalytic performance has also been revealed. The introduction of PW12 can efficiently enhance the photocatalytic activity of Bi2WO6, because of increasing the efficiency of charge separation and restraining the fast electron-hole recombination in Bi2WO6.