Enhanced visible photocatalytic degradation of diclofenac by ultrasound-assisted prepared C and N co-doping TiO ₂

Abstract In this study, carbon and nitrogen co-doped TiO 2 nanocomposites (C–N–TiO 2 ) were successfully synthesized by the hydrothermal and low temperature calcination method with ultrasound (US) assistance for photocatalytic degradation of diclofenac (DCF). It was found that the introduction of US at two particular synthesis steps would obviously improve the photocatalytic properties of C–N–TiO 2 . Characterizations indicated the enhancement was owing to the integrative effects of the holonomic crystal structure and special morphology properties. Under LED visible light irradiation of 450 nm wavelength, C–N–TiO 2 could achieve excellent degradation rate of 97 % at 3 h with dosage of 0.4 g L −1 . The role of full-process sonication to affect the properties of C–N–TiO 2 was also revealed. The result of this study is expected to provide a feasible and easy way to improve the ability of semiconductor catalysts for water purification.