Optimizing photoelectrocatalytic Efficiency: Synergistic activation of peroxymonosulfate by CuFeO2/BiVO4 composites for antibiotic removal

The BiVO 4 photoanode and CuFeO 2 materials were synthesized via electrodeposition and hydrothermal methods, respectively, and the p-n type 2-CBVO (CuFeO 2 /BiVO 4 ) composite photoanode was prepared using a spin-coating technique. The degradation performance of the composite photoanodes was evaluated in a PEC-coupled PMS (peroxymonosulfate) activation system using levofloxacin (LVF) as the target pollutant. The 2-CBVO photoanode achieved a degradation efficiency of 78.8 % for LVF (15 ppm) within 30 min, representing a 45.1 % improvement over the BiVO 4 photoanode. The pseudo-first-order rate constant for the degradation of LVF was determined to be 4.43 × 10 −1 min −1 . Photoelectrochemical analysis confirmed that CuFeO 2 loading and PMS introduction enhanced photogenerated carrier separation, promoting LVF degradation. Radical trapping experiments indicated that h + , OH, SO 4 − and O 2 − were the primary reactive species in the degradation process. Both theoretical calculations and experimental results confirmed that the internal electric field at the composite interface directs from BiVO 4 to CuFeO 2 , facilitating electron transfer from CuFeO 2 to BiVO 4 and onward to the cathode surface via the external circuit. Cyclic stability tests demonstrated that the 2-CBVO composite photoanode retained 90.0 % of its activity after five cycles, indicating excellent stability and significant potential for water treatment applications.