Multiple regulations of Mn-based oxides in boosting peroxymonosulfate activation for norfloxacin removal

In this work, a spinel cobalt doped manganese oxide catalyst with the morphology of rambutan-like hollow sphere was successfully obtained by a facile carbon sphere-templated and post-calcined strategy. Multiple strategies such as visible light assistant, Jahn-Teller (J-T) effect, Co-Mn synergistic interaction, and abundant active sites exposed have been considered together in this elaborated system. Theoretical calculation was performed to simulate and analysis the catalyst crystal properties. Visible light assistant cobalt doped manganese oxides possessed a much superior performance and the CoMn1/3 sample exhibited the highest catalytic activity. Norfloxacin (NOR) degradation paths were analyzed by HPLC-MS and the visible light-PMS activation coupling mechanism on cobalt manganese oxides was finally speculated from numerous aspects. This study not only provides the multiple regulations of catalysts from the electronic states and morphology, but also demonstrates the promising potential of various coupling techniques integrated in the contaminant remediation.