Synthesis of a ternary Bi2O3/CQDs/rGO photocatalyst to active peroxymonosulfate for the removal of tetracycline hydrochloride

Abstract

In this paper, the ternary Bi₂O₃/CQDs/rGO photocatalyst was synthesized by a solvothermal method. The as-fabricated Bi₂O₃/CQDs/rGO composites showed stronger visible-light response and higher photocatalytic activity. In order to further enhance the degradation efficiency of tetracycline hydrochloride, Bi₂O₃/CQDs/rGO was used to activate peroxymonosulfate under visible-light irradiation. The degradation efficiency increased sevenfold, indicating that the synergistic effect of photocatalysis and peroxymonosulfate activated by photogenerated electrons could clearly increase the degradation efficiency of tetracycline hydrochloride. In addition, the photocatalytic mechanism was further proposed and verified by radical quenching experiments and electron paramagnetic resonance analysis. Thus, this study provides a new idea for the photocatalytic application of Bi₂O₃/CQDs/rGO and a contribution to the degradation of antibiotics to avoid polluting the water environment.