A facile fabrication of Ag_2O-Ag/ZnAl-oxides with enhanced visible-light photocatalytic performance for tetracycline degradation

摘要

A facile and low-cost method to prepare novel Ag2O-Ag/LDO photocatalysts was demonstrated, where the Ag2O/Ag nanoparticles were decorated on the ZnAl oxide (LDO) supports. The LDO supports were obtained by calcining their ZnAl layered double hydroxide precursor (LDH) at different temperatures. The structure, composition, morphology and optical and electrochemical properties of the as-prepared Ag2O-Ag/LDO were characterized using various techniques. Under visible light irradiation, the Ag2O-Ag/LDO showed higher photoactivity and stability of tetracycline (TC) degradation than pure Ag2O-Ag. Especially, the Ag2O-Ag/LDO5 (Ag2O-Ag/LDO calcined at 500 degrees C) had the most excellent photoactivity with the highest rate constant k (0.0242 min(-1)), suggesting that the photocatalytic activity depended on the calcination temperature. The enhancement of the photocatalytic performance was attributed to the formation of the heterostructure between Ag2O/Ag and ZnO, the strong visible-light absorption and outstanding separation efficiency of photoinduced electron-hole pairs under visible light irradiation.