Synthesis of Ag/BiOBr/CeO composites with enhanced photocatalytic degradation for sulfisoxazole.

A novel Ag/BiOBr/CeO composite was successfully prepared for the first time, which had excellent performance in degrading sulfisoxazole (SSX) under visible light irradiation. The as-prepared samples were characterized by SEM, XRD, UV-vis DRS and BET et al. The composite of 10% Ag/BiOBr/CeO showed the best photocatalytic activity and more than 99.5% SSX can be removed within 20 min. It exhibited the highest k value of 0.2428 min, which was about 39.7 times higher than pure BiOBr (6.11 × 10 min) and 22.1 times higher than BiOBr/CeO (1.09 × 10 min), respectively. The addition of Ag significantly improved the absorption rate of visible light and the separation rate of photogenerated electron-hole pairs. The initial pH and dosage of samples could have an influence on the photocatalytic activity. The radical trapping experiments proved that ·O and h were the main active species involved in photocatalytic degradation. Finally, the synthesized catalyst maintained excellent photocatalytic activity after 5 repeated cycles, which indicated the extraordinary stability and recyclability of Ag/BiOBr/CeO.