Co and N co-doped carbon nanotubes catalyst for PMS activation: Role of non-radicals

Metal-nitrogen-carbon catalysts demonstrate significant advantages in the remediation of water environments. Here, a cobalt-nitrogen-carbon catalyst (Co(1.5)-NCNT) with abundant Co-Nx active sites and excellent electron transfer capability was prepared via a simple method and used to activate peroxymonosulfate (PMS) for efficient removal of Acetaminophen (APAP). As a result, the Co(1.5)-NCNT/PMS system removed 100% of APAP within 10 min. The reaction process characterization suggested that PMS is adsorbed by Co(1.5)-NCNT to form a Co(1.5)-NCNT-PMS complex, which accelerates PMS activation. Additionally, the singlet oxygen (1O2) generated by PMS activation can effectively attack electron-rich contaminants, facilitating the rapid degradation of APAP. Furthermore, Co(1.5)-NCNT/PMS exhibits strong environmental adaptability, maintaining high catalytic performance in complex water environments for the effective degradation of various pollutants. This study elucidates the properties of Co-Nx active sites in the Co(1.5)-NCNT/PMS system and the activation mechanism of PMS, providing new insights into the removal of pollutants through non-radical pathways.