Construction of BiFeO3/BiVO4 composite photoanode and its application in PMS-assisted photoelectrocatalytic degradation of levofloxacin

Antibiotic pollutants such as levofloxacin (LVF) pose serious threats to ecosystems and human health due to their persistence in aquatic environments, making their efficient removal a great challenge. In this study, a BiFeO 3 /BiVO 4 heterojunction photoanode was rationally designed for the photoelectrocatalytic (PEC) degradation of levofloxacin (LVF) in the presence of peroxymonosulfate (PMS). Under visible light irradiation and a 0.6 V bias, the BiFeO 3 /BiVO 4 photoanode coupled with PMS achieved 78 % LVF degradation, markedly surpassing bare BiVO 4 (≈44 %), with excellent mineralization and stability, retaining > 72 % efficiency after four cycles. Radical quenching experiments revealed the synergistic roles of SO 4 •− , ‧O 2 − , ‧ OH , and h + . To clarify the PMS activation pathway, a dual-chamber H-type reactor with a proton exchange membrane was employed, confirming that PMS activation originated from photogenerated electrons at the photoanode, while the cathode contribution was negligible. Photoelectrochemical analyses (OCP, DPV, EIS, i–t) further demonstrated the adsorption–activation–electron capture behavior of PMS. These findings highlight BiFeO 3 /BiVO 4 as a promising photoanode for PMS-assisted PEC degradation of antibiotics, offering an effective strategy for water purification.