Photocatalytic activity of composites in an AgBr–Ag2CrO4 system prepared by a grinding method with and without washing

Abstract

Various composites of photocatalysts in the AgBr–Ag2CrO4 system were synthesized via a simple grinding method with and without a washing process. After the starting materials were ground together, the resulting powders showed three phases: AgBr, Ag2CrO4, and KNO3. When these products were washed with deionized water, the KNO3 did not present in the final product. Under visible light irradiation, the prepared photocatalysts can degrade the rhodamine B and reactive orange dyes solutions. Experimental results showed that the KNO3 which was the impurity phase in this system did not affect the photocatalytic activities of prepared photocatalysts. The 0.9AgBr–0.1Ag2CrO4 composite exhibited the best photocatalytic activity and the photocatalytic enhancement of this compound could be attributed to a charge separation. Investigation of inhibitory activity using scavengers confirmed that photogenerated holes and superoxide anion radicals were the primary reactive species produced during the photocatalytic process.