Visible light response ZnO–C3N4 thin film photocatalyst

Nanoflower-like ZnO–C3N4 thin film with a porous net structure was successfully synthesized by a simple chemical corrosion method. The prepared ZnO–C3N4 thin films presented remarkable photocatalytic activities for the degradation of methyl orange under visible light irradiation, and more than 90% methyl orange was removed from water by ZnO–C3N4 composite. Meanwhile, the ZnO–C3N4 composite presented an enhanced photocatalytic stability. The loading content of C3N4 had a great effect on the photocatalytic performance. Moreover, the photocatalytic activities were higher in acidic media than those in alkaline conditions. The adsorption of methyl orange was enhanced, and the recombination of photogenerated electrons and holes was suppressed with a suitable content of C3N4. However, too much loading content of C3N4 resulted in a poor dispersion of C3N4 as the aggregated C3N4 can behave as recombination centers. In addition, the prepared ZnO–C3N4 thin film can be used for the water splitting in water–methanol system under simulated solar light irradiation.