ZIF-67-derived carbon@Co3S4/CoSO4/MnO polyhedron to activate peroxymonosulfate for degrading levofloxacin: Synergistic effect and mechanism

In this work, a carbon-doped Co 3 S 4 /CoSO 4 /MnO catalyst (C@CoSOMn) was prepared in this work by using ZIF-67 as the template. The prepared catalyst was used to degrade levofloxacin (LEVO) by activating peroxymonosulfate (PMS). The optimized catalyst could degrade 97.73 % LEVO within 20 min with a rate constant of 0.294 min −1 . The combination of water-soluble CoSO 4 and Co 3 S 4 made more Co sites accessible to PMS for lasting decomposition to produce active species. Moreover, Mn species with low redox potential could promote the regeneration of Co 3+ and the activation of PMS. The doped carbon could facilitate the transfer of electron. Superoxide radicals (⋅O 2 − ), bulk and surface hydroxyl radicals (•OH), surface sulfate radicals (SO 4 •− ), and electron transfer process, especially the singlet oxygen ( 1 O 2 ) were involved in the LEVO degradation. This study sheds light on the synergism between the Co-based sulfide and the Mn oxide in the activation process of PMS, and might prompt the development of other ZIF-67-derived hybrid materials for environmental remediation.