Preparation of Fe3O4@ACF Composite Catalytic Electrode and Study of Its Degradation of Antibiotics.

Antibiotics are extensively used in intensive livestock farming for disease prevention, resulting in the discharge of antibiotic-contaminated wastewater into aquatic environments. Addressing this issue, electrocatalytic oxidation has emerged as a promising alternative to conventional chemical oxidation due to its cost-effectiveness and minimal secondary pollution. Central to this technology is the development of catalytic electrodes with high specific surface area and superior electrocatalytic activity. In this work, an Fe3O4-modified activated carbon fiber electrode (Fe3O4@ACF) was fabricated via a co-precipitation method. The Fe3O4@ACF electrode exhibited a hierarchical porous structure with a specific surface area of 940.2 m2/g, and demonstrated significantly enhanced oxygen reduction reaction activity with a current density of 21.8 mA·cm-2 at -3.25 V vs. Ag/AgCl, which is 2.3 times higher than that of pristine ACF. EIS analysis revealed a low charge transfer resistance of 7.18 Ω, indicating improved electron transfer kinetics. In electro-Fenton degradation of tetracycline, the electrode achieved 82% removal within 120 min with a first-order rate constant of 0.01335 min-1, and maintained over 94% of its initial activity after ten cycles. This study offers a viable and sustainable strategy for the efficient treatment of antibiotic-containing medical wastewater.