Rhombic dodecahedral ZIF-8-supported CuFe2O4 triggers sodium percarbonate activation for enhanced sulfonamide antibiotics degradation: Synergistic roles of heterostructure and photocatalytic mechanisms

Pollution from extensive sulfonamide antibiotic use is a critical research focus, particularly in the remediation of these antibiotics using composite materials. This study employed a CuFe 2 O 4 /ZIF-8 composite to activate sodium percarbonate (SPC) for the photo-Fenton-like degradation of the sulfonamide antibiotic sulfamethoxazole (SMX). The optimal conditions for SMX degradation were determined using the CuFe 2 O 4 /ZIF-8/SPC/Vis system: a ZIF-8 composite ratio of 40 %, catalyst dosage of 0.15 g/L, SPC concentration of 0.8 mM, and initial pH of 3.0, achieving complete SMX removal within 30 min. After five cycle tests, the leaching rates of copper and iron ions were 0.179 mg/L and 0.376 mg/L, respectively, significantly lower compared to the use of CuFe 2 O 4 alone as the catalyst (Cu: 0.46 mg/L, Fe: 1.43 mg/L). The radicals present in the system were identified, with their contribution rates ranked from highest to lowest as follows: ·OH > h + > ·O 2 – > CO 3 · - > 1 O 2 . Further mechanistic investigations revealed that the heterogeneous structures in CuFe 2 O 4 /ZIF-8 enhanced the efficiency of the photo-Fenton-like reaction by facilitating electron transfer. This study introduced an innovative approach for antibiotic treatment using the CuFe 2 O 4 /ZIF-8 composite under visible light irradiation and broadened the technical framework of SPC-based advanced oxidation processes (AOPs) for treating wastewater.