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 Bi4O5Br2 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 Bi4O5Br2 nanosheets towards the target antibiotics under visible light irradiation. rGO/Bi4O5Br2 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 Bi4O5Br2 nanosheets. The capture experiments and ESR data show that center dot O-2(-), OH center dot and h(+) are the main active species that participated in the photodegradation system. This work provides a simple strategy to integrate rGO with BixOyXz (X = Cl, Br, I) nanosheets to construct effective photocatalysts for the degradation of antibiotics. (C) 2020 Elsevier Ltd. All rights reserved.

Automated summary

The integration of reduced graphene oxide (rGO) with Bi4O5Br2 nanosheets enhances the adsorption and photocatalytic properties of the photocatalyst towards antibiotics under visible light irradiation. The nanocomposite containing 1.0 wt% rGO shows optimal adsorption and photocatalytic activity towards ciprofloxacin, norfloxacin, and tetracycline. Active species such as O•2-, OH•, and h+ were identified as main participants in the photodegradation system.