Pharmaceutical pollutants such as clofibric acid pose significant risks to aquatic environments and human health. In this
study, a bifunctional cathode (CF@Fe3O4) was synthesized by anchoring Fe3O4 nanoparticles onto carbon felt via a solvothermal method. The material was characterized using scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy. The CF@Fe3O4 cathode was then evaluated in a heterogeneous electro-Fenton system
for clofibric acid degradation under varying pH and current conditions using platinum and boron doped diamond anodes.
Using the CF@Fe3O4/Pt pair, the highest mineralization efficiency (82%) was achieved at pH 3 and 50 mA after 5 h,
whereas higher current intensities resulted in decreased mineralization. In contrast, the CF@Fe3O4/BDD system showed
enhanced performance with increasing current, achieving 99% mineralization at 300 mA and pH 3. The BDD anode also
enabled mineralization efficiencies above 90% across a broad pH range (3–8), along with faster reaction kinetics and
improved energy efficiency. Fe3O4 loading promoted electron transfer and mitigated mass transport limitations, significantly improving degradation rates. Additionally, a small amount of Fe ion leach (1 mg L−1) at pH 3 facilitated supplementary •
OH production through the homogeneous electro-Fenton process. Radical scavenging experiments identified •
OH
as the dominant reactive species, with supporting contributions from O2
•− and SO₄•−. The CF@Fe3O4 cathode maintained
stable performance over five reuse cycles, demonstrating its potential as a durable, pH-independent, and environmentally
friendly electrode material for the removal of persistent organic pollutants.