Magnetically Recyclable Fe3O4/Cu2O Heterojunction for Photo-Assisted Peroxymonosulfate Activation Toward Bisphenol A Degradation

Efficient removal of bisphenol A (BPA) from aquatic environments is urgently needed due to its toxicity and persistence. Peroxymonosulfate (PMS)-based advanced oxidation processes offer a promising solution, and their effectiveness critically depends on catalysts with efficient charge transfer and stable interfacial properties. Herein, a magnetically recyclable Fe 3 O 4 /Cu 2 O heterojunction was constructed via covalent esterification between polydopamine and citrate layers on each component. Under optimized conditions (catalyst: 90 mg/L, PMS: 2.0 g/L, BPA: 20 mg/L, pH 11), the heterojunction achieved 98% BPA removal within 60 min and retained over 90% of its initial activity after five cycles. Mechanism investigation confirmed •OH and SO 4 • − were the dominant reactive species and elucidated a plausible BPA degradation pathway. This work provided an efficient and recyclable photocatalyst for water treatment and establishes an interfacial engineering strategy for constructing advanced catalysts with promising applications in the environmental and energy fields. Graphical Schematic illustration of the proposed mechanism for PMS activation and BPA degradation over the Fe 3 O 4 /Cu 2 O heterojunction.