Flower-like bentonite-based Co3O4 with oxygen vacancies-rich as highly efficient peroxymonosulfate activator for lomefloxacin hydrochloride degradation

In this work, a flower-like structure and oxygen vacancies (OVs) enriched bentonite-based Co 3 O 4 (Co 3 O 4 /Bent) was successfully prepared, and then was applied as a new activator of peroxymonosulfate (PMS) to degrade lomefloxacin hydrochloride (LOMH). The characterization results demonstrated that Co 3 O 4 /Bent had a flower-like structure, high Co(Ⅱ)/Co(III) ratio and high OVs content. The optimal composite of Co 3 O 4 /Bent held a high catalytic activity in LOMH degradation, and approximately 87.2 % of LOMH (30 mg/L) could be degraded at 60 min by using Co 3 O 4 /Bent (0.2 g/L) to activate PMS (3.0 mmol/L). And the quenching experiments revealed that 1 O 2 , ·OH, SO 4 ·- and ·O 2− were the active species and 1 O 2 played a main role in the LOMH degradation process. The possible degradation pathways were revealed based on DFT calculation and LC-MS analysis. This work suggested that the Co 3 O 4 /Bent composite was an efficient catalyst to activate PMS to treat LOMH in wastewater.