Rapid Electrochemical Removal and Preliminary Detoxification of Moxifloxacin in Water Using a Ce- and F-Co-Doped Ti/Ni/PbO2 Anode

Moxifloxacin (MOX), a fluoroquinolone antibiotic and contaminant of emerging concern frequently detected in aquatic environments, poses potential ecological risks due to its persistence and residual antibacterial activity. In this study, a Ce- and F-co-doped Ti/Ni/PbO2 anode was fabricated and evaluated for the rapid electrochemical removal of MOX from water. Ce–F co-doping refined the PbO2 coating, increased the oxygen evolution potential, and reduced the corrosion current density, thereby improving electrocatalytic activity and short-term stability. Under optimized conditions (40 mA cm−2, 0.125 M Na2SO4, pH 7, and 2.5 mg L−1 MOX), 99.8% MOX removal was achieved within 60 s, following pseudo-first-order kinetics. Radical quenching experiments and electron paramagnetic resonance spectroscopy suggested that hydroxyl radical-mediated indirect oxidation was the dominant degradation pathway. The process also achieved partial mineralization, with 20.2% TOC removal, an electrochemical energy consumption of 0.21 kWh g−1 TOC, and a mineralization current efficiency of 22.4%. The net inhibition-zone diameter against Escherichia coli decreased by 92.0%, while Pb leaching remained at 0.00442 mg L−1 after short-term cyclic operation. Near-complete MOX removal was also achieved in reclaimed water and secondary clarifier effluent within 100–160 s. These results demonstrate the potential of the Ti/Ni/Ce–F–PbO2 anode for rapid electrochemical treatment of MOX-contaminated water and support its further evaluation for advanced treatment of antibiotic-containing effluents.