Preparation of Ag@AgCl/g-C3N4/TiO2 porous ceramic films with enhanced photocatalysis performance and self-cleaning effect

We report a novel method to prepare translucent and stable Ag@AgCl/g-C3N4/TiO2 ceramic films having strong photocatalytic activities and self-cleaning capabilities under light irradiation. Colloidal silica was used as an inorganic binder and P25 TiO2 was added as a hydrophilicity enhancer without which a smooth coating was not achievable. Ag@AgCl of particle size around 30 nm, was synthesized by in-situ oxidation of nano-silver particles in porous g-C3N4/TiO2 films. Optimal conditions for Ag@AgCl/g-C3N4/TiO2 preparation in terms of strongest photocatalysis were established by tests on Rhodamine B degradation under visible and full spectral irradiations. A good adhesion strength of the porous films on glass substrate was achieved. Stability and reusability of the films were assessed by cycling tests. Possible photocatalytic mechanisms are proposed based on the basis of trapping experiments. Systematic characterization of the film suggests that the in-situ oxidation is an effective and practical method to produce nanoscale Ag@AgCl.