Enhanced peroxymonosulfate activation for antibiotic and heavy metal removal using ZIF-67-derived magnetic Ni/Co-LDH@NC: Bimetallic electronic synergy and oxygen vacancy effects

Designing advanced bimetallic catalysts is essential to improving peroxymonosulfate (PMS) activation. Herein, a novel magnetic nickel/cobalt-layered double hydroxide decorated nitrogen-doped carbon (Ni/Co LDH@NC) catalyst we synthesized using carbonized ZIF-67 as a template for simultaneous removal of sulfamethoxazole (SMX) and Pb(Ⅱ) by PMS activation. The synthesized Ni/Co LDH@NC achieved complete degradation of SMX within 20 min and adsorbed Pb(Ⅱ) at 90.3 mg g −1 in 2 h. Notably, in simulated mixed wastewater, Ni/Co LDH@NC removed 100 % of SMX and simultaneously absorbed 84 % of Pb(Ⅱ) within 60 min. Density functional theory (DFT) studies revealed that synergistic Ni-Co sites and “bridging oxygen” vacancies enhanced electron transfer to PMS, facilitating O-O bond cleavage. The catalyst maintained high performance after four cycles, with over 85 % SMX degradation and 80 % Pb(Ⅱ) removal. This study highlights the potential of MOF-derived catalysts for efficient, simultaneous remediation of antibiotic and heavy metal pollutants, contributing to advanced wastewater treatment.