Performance and Mechanism of In Situ Prepared NF@CoMnNi-LDH Composites to Activate PMS for Degradation of Enrofloxacin in Water

To overcome the disadvantage of difficult recovery of powder catalysts and improve catalyst utilization, the selection of foam metal substrates as supports can reduce the difficulty of material recovery and effectively inhibit the leaching of metal ions. Herein, CoMnNi-layered double hydroxide (LDH) derived from Co-Mn ZIF was immobilized onto nickel foam (NF) through in situ synthesis. The results of XRD and SEM analyses of the samples indicated that the LDH was successfully grown on the nickel foam matrix, and the material could maintain its original morphology to the maximum extent after loading. By comparing the XPS of the material before and after the reaction, it was confirmed that the surface hydroxyl group and C=O of the material were involved in the activation of peroxymonosulfate (PMS). The results of the quenching reaction showed that SO4•− and 1O2 are the main active substances in the oxidation of enrofloxacin (ENR). When the dosage of NF@CoMnNi-LDH was 0.4 g/L, the pH of the solution was 6.82, and when the dosage of PMS was 2.0 mM, the degradation rate of ENR reached 82.6% within 30 min. This research offers novel insights into the degradation of antibiotics from water using a monolithic catalyst supported by metal foam.