Construction of CuBi2O4/Bi2MoO6 p-n heterojunction with nanosheets-on-microrods structure for improved photocatalytic activity towards broad-spectrum antibiotics degradation

Abstract Focused on the remediation of water bodies which polluted by the antibiotics, a novel hierarchical structure CuBi2O4/Bi2MoO6 p-n heterojunction photocatalyst with 2D nanosheets on 1D microrods structure were synthesized through a facile solvothermal method. The broad-spectrum antibiotics, including tetracyclines and quinolones drugs, were used as the target pollutants, which were degraded under visible light to evaluate photocatalytic performance of the prepared photocatalysts. Notably, the 10 wt% CuBi2O4/Bi2MoO6 photocatalyst displays the optimum photocatalytic performance in the degradation of tetracycline, oxytetracycline, chlortetracycline and ciprofloxacin (100 mL, 20 mg/L; 72.8%, 74.0%, 74.4% and 36.7% degradation rates and 34.4%, 52.4%, 48.2% and 25.5% mineralization rates within 60 min) under visible irradiation (λ > 420 nm). The photocatalytic reaction mechanism over CuBi2O4/Bi2MoO6 was also uncovered in detail by the active species trapping experiments and electron spin resonance (ESR) technique. Finally, the possible photodegradation pathways of TC was proposed on the basis of the intermediates detected by liquid chromatography-mass spectroscopy (LC–MS).