Oxygen vacancy-mediated Bi2WO6/FeOOH heterojunction for efficient photo-Fenton degradation antibiotics and synergistic sterilization

Abstract

Photo-Fenton as the advanced oxidation technology shows great potential in water purification, which is limited by the sluggish reaction kinetics. Herein, oxygen vacancy-mediated Bi₂WO₆/FeOOH (Vo-BWO/FeOOH) heterojunction has been successfully constructed and performs superior performance for degradation antibiotic wastewater and antibiotic resistant bacteria (ARB) inactivation. The optimal photo-Fenton degradation rate for TCH achieves 0.0833 min⁻¹ over oxygen vacancy-rich BWO/FeOOH (Vo-r-BWO/FeOOH). The degradation rate of tetracycline reached 100 % within 60 min, while the removal efficiency of E. coli resistant to tetracycline, ampicillin, and kanamycin was 94.1 % at 80 min. Moreover, Vo-r-BWO/FeOOH heterojunction also exhibits excellent durability, strong removal ability for multiple antibiotics and exceptional activity in a practical water environment. The comprehensive study of experiment and density functional theory (DFT) calculations confirms that the synergistic effect of oxygen vacancies accelerates the interfacial charge carriers’ migration and adsorption-activation of H₂O₂. Finally, the degradation pathway and toxicity of intermediates have been ascertained. This work provides a valuable strategy for the remediation of antibiotic wastewater resources.