Synthesis and characterization of AgBr/AgNbO3 composite with enhanced visible-light photocatalytic activity

A novel AgBr/AgNbO3 composite was synthesized by a two-step method. The physical and chemical properties of catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), energy dispersive spectrometer (EDS), diffuse-reflection spectra (DRS), and photocurrent techniques. The photocatalytic performance of the samples was evaluated by photocatalytic oxidation of methylene blue (MB) dye under visible-light irradiation. The XRD, SEM-EDS, and XPS analyses indicated that the heterojunction structure had formed in the composite. The DRS analysis showed that AgBr formed on the surface of AgNbO3 had promoted the optical absorption in the visible region and made it possible to enhance the photocatalytic activity. The results indicated that the AgBr/AgNbO3 heterojunction had exhibited a much higher photocatalytic activity than the pure AgNbO3. The mechanism of the AgBr/AgNbO3 composite with enhanced heterojunction photocatalytic activity was researched.