Synergistic Photo-self-Fenton Catalysis in a 3D PES-Confined Heterojunction Achieving 500-h Stable Antibiotic Degradation

Photo-self-Fenton catalysis offers a promising route for antibiotic wastewater treatment, yet powder catalysts suffer from difficult recovery, particle loss, aggregation, and separation of H2O2-generation and Fe-activation sites, limiting interfacial synergy and durability. Herein, a three-dimensional (3D) polyethersulfone(PES)-confined resorcinol-formaldehyde/MIL-88A(Fe) (R8) heterojunction (R8@PES) was developed for visible-light-driven tetracycline hydrochloride (TC) degradation. The porous PES scaffold immobilized R8 powders into recoverable 3D spheres and spatially confined resorcinol-formaldehyde (RF) and MIL-88A(Fe) within an interconnected network, suppressing aggregation while maintaining close contact between H2O2-producing RF sites and Fe-active MIL-88A(Fe) sites. The porous architecture further enhanced light utilization via internal reflection/scattering and facilitated TC enrichment near catalytic interfaces through accessible pores and moderate adsorption. As a result, optimized R8@PES achieved 98.7% TC removal within 80 min and retained over 75% degradation efficiency after 500 h of continuous-flow operation. Mechanistic results revealed that RF promoted in situ H2O2 generation, while MIL-88A(Fe) activated H2O2 via Fe2+/Fe3+ cycling to produce ·OH, accompanied by ·O2– and 1O2. LC-MS, toxicity prediction, antibacterial assays, and wheat chlorophyll fluorescence tests confirmed progressive degradation and detoxification. This work provides an effective 3D confinement strategy for durable photo-self-Fenton antibiotic remediation.