Efficient charge separation of Ag2CO3/ZnO composites prepared by a facile precipitation approach and its dependence on loading content of Ag2CO3

To further improve the separation of photo-induced charge carriers, Ag2CO3 was employed to couple with ZnO. In this paper, Ag2CO3 was facilely deposited on the surface of ZnO through a precipitation method. The effects of loading content of Ag2CO3 on the charge separation of Ag2CO3/ZnO composites and their photocatalytic performance were studied by the means of surface photovoltage spectroscopy (SPS). Coupling of ZnO with Ag2CO3 can greatly accelerate the charge separation under the simulated solar light irradiation, supported by the SPS results. The enhancement of charge separation rate and photocatalytic activities of Ag2CO3/ZnO composites notably depends on the loading content of Ag2CO3. With the optimal theoretical Ag/Zn molar ratio of 3/100, the composite exhibits the highest charge separation rate and photocatalytic activity under the simulated solar light illumination. To better comprehend the improved separation of the photo-induced charge carriers, a Z-scheme charge separation mechanism was proposed.