Facile synthesis of AgIO 3 /AgBr composite with enhanced photocatalytic activity under visible-light irradiation

The efficient visible-light-driven AgIO3/AgBr photocatalyst was successfully synthesized by an in-situ anion-exchange method at room temperature. The scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV–vis diffuse reflection spectroscopy (DRS) were used to characterize the obtained samples. The photocatalytic activities of the as-prepared heterojunctions were estimated by decomposing the organic dye RhB under visible-light irradiation (λ > 420 nm). Compared with pure AgBr and AgIO3, the AgIO3/AgBr compounds showed dramatically improved visible-light photocatalytic activity. Besides, the results also revealed that 20% AgIO3/AgBr exhibited the best photocatalytic activity, which could decompose the RhB completely in 24 min. The enhanced photocatalytic activity of the composites could be ascribed to the high separation rate of the photoinduced electron–hole pairs in the heterojunction structure. Moreover, the radical trap experiments were also carried out which confirmed that h+ played the major role in RhB photodegradation. The possible mechanism of RhB degradation on the AgIO3/AgBr composite was also discussed according to the results of the experiments and the performance of the obtained photocatalysts.