Highly efficient antibiotic decontamination and biotoxicity elimination with activity-stability considerations via...

The pollution of emerging persistent organic contaminant antibiotic is becoming a significant environmental concern, which necessitates efficient treatment techniques. Peroxymonosulfate (PMS)-based advanced oxidation process holds promise for the removal of organic contaminants, whereas acquiring a heterogeneous catalyst with both high activity and remarkable stability still remains challenging. Herein, the feasibility and performance of core-shell CoS@nitrogen-doped hollow carbon (CoS@NHC) as PMS activator for metronidazole (MNZ) degradation and biotoxicity elimination have been explored. Experimental results indicated that the CoS@NHC-650/PMS system exhibited excellent performance, achieving 100 % MNZ removal within 4 min and a very small cobalt leaching. Moreover, the CoS@NHC-650/PMS system exhibited additional merits such as great reusability and broad applicability, and biotoxicity elimination (demonstrated through software evaluation, soybean growth and zebrafish culture experiments). The MNZ degradation routes were figured out via intermediate product analysis and density functional theory modeling. Mechanism investigation uncovered that radical and non-radical pathways played a synergistic role, and the main reactive species included SO₄^‧-, ¹O₂ and Co(IV)=O. This study overcomes the common activity-stability trade-off and presents a promising heterogeneous catalyst towards PMS activation for degradation of organic contaminants and biotoxicity elimination.