Ion-exchange of Cu2+ promoted layered perovskite K2La2Ti3O10 for photocatalytic degradation chlorobenzene under simulated solar light irradiation

Abstract

The layered perovskite, K2La2Ti3O10was prepared by sol-gel method. Ion-exchange of Cu2+ was prepared to improve the photocatalytic activity of K2La2Ti3O10for chlorobenzene degradation under simulated solar light irradiation. The original K2La2Ti3O10and Cu2+/K2La2Ti3O10were characterized by power X-ray diffraction, UV-visible diffuse reflectance spectroscopy, and specific surface area measurement. The XRD analysis shows that Cu2+ ions is incorporated in place of K+ ions and the grain growth is inhibited by ion-exchange. With the rise of calcination temperature, more interlayer Cu2+ was converted into new crystal phase CuO. The degradation ratio reaches 51.1% on Cu2+/ K2La2Ti3O10calcined at 500 °C in air, which is higher 16.9% than the original K2La2Ti3O10. It should be ascribed to the narrow interlayer distance, the formation of CuO, smaller grain size, and the high visible light absorption on the surface of Cu2+/K2La2Ti3O10calcined at 500°C. It is found that the exposure of CO2 could promote the photocatalytic activity of Cu2+/K2La2Ti3O10. It also suggests that CO2 is involved in the reduction to form benzaldehyde during decomposition of chlorobenzene.