Cu-based composite materials derived from MOFs for visible light PMS activation in tetracycline removal

The degradation of recalcitrant antibiotics through the activation of peroxymonosulfate (PMS) is an important branch of advanced oxidation processes (AOPs), with widespread attention given to the application of metal-organic frameworks (MOFs) in this field. The article successfully synthesized CuxO/N-doped carbon/Cu-MOF (CuxO/NC/Cu-MOF) nanocomposites by low-temperature thermal treatment of Cu-MOF precursors. Compared with the original MOF, these partially decomposed composite materials exhibit significantly stronger catalytic activity towards PMS, efficiently removing organic pollutants such as tetracycline (TC). After optimization, the sample treated at 400 °C, under visible light with PMS assistance, achieves an impressive degradation rate, almost completely degrading a 50 mL TC solution (10 mg/L) after 80 min. This achievement surpasses the degradation rate observed with the original Cu-MOF by 2.1 times. In the composite system of CuxO/NC/Cu-MOF+PMS+Vis, the significant enhancement of activity is credited to the effective spatial separation of photogenerated electrons and holes, as well as the utilization of 1O2 as the primary active oxygen species. This work provides a simple preparation strategy for the development of Cu-based PMS activators with excellent photocatalytic performance.