Ion-exchange preparation for visible-light-driven photocatalyst AgBr/Ag2CO3 and its photocatalytic activity

The AgBr/Ag2CO3 composite was synthesized by an ion-exchange reaction. The physical and chemical properties of the catalysts were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), 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, TEM, and XPS analyses indicated that the heterojunction structure had been obtained. The results indicated that the AgBr/Ag2CO3 heterojunction had exhibited a much higher photocatalytic activity than the pure Ag2CO3. The enhancement of photocatalytic activity was related to the efficient separation of electron–hole pairs because of the stagger band potentials between AgBr and Ag2CO3.