Reduced graphene oxide/Bi4O5Br2 nanocomposite with synergetic effects on improving adsorption and photocatalytic activity for the degradation of antibiotics

A photocatalyst based on the integration of reduced graphene oxide (rGO) with Bi 4 O 5 Br 2 nanosheets was facilely prepared and was confirmed by transmission electron microscope , scanning electron microscope, X-ray diffraction and Raman spectroscopy . The integration of rGO can effectively improve the adsorption and the photocatalytic properties of Bi 4 O 5 Br 2 nanosheets towards the target antibiotics under visible light irradiation. rGO/Bi 4 O 5 Br 2 nanocomposite containing 1.0 wt% of rGO exhibits the optimal adsorption and photocatalytic activity towards ciprofloxacin (CIP), norfloxacin (NOR) and tetracycline (TC). The removal efficiencies of CIP, NOR and TC are 97.6%, 80.7% and 98.7%, which are higher than that obtained with Bi 4 O 5 Br 2 nanosheets. The capture experiments and ESR data show that ·O 2 − , OH· and h + are the main active species that participated in the photodegradation system. This work provides a simple strategy to integrate rGO with Bi x O y X z (X = Cl, Br, I) nanosheets to construct effective photocatalysts for the degradation of antibiotics.