ZnWO4–Cu system with enhanced photocatalytic activity by photo-Fenton-like synergistic reaction

A novel coupled system of ZnWO4–Cu, combining two different advanced oxidation processes of photocatalysis and Fenton-like for the degradation of organic dyes, was successfully synthesized. The as-synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS). The nanosized ZnWO4–Cu samples exhibited much higher catalytic activity than pure ZnWO4. In the presence of the ZC-0.2, the MB solution was completely degraded (the degradation ratio reached 97.79%); while for the ZC-0, the degradation ratio was only 72.29%. The effects of the amount of Cu on the photocatalytic performance of ZnWO4–Cu were investigated in detail. The result showed that the synergistic effect between Cu and ZnWO4 played a key role. The possible mechanism of the synergistic system was proposed.