Iron-copper bimetallic metal-organic frameworks for efficient Fenton-like degradation of sulfamethoxazole under mild conditions.

Iron and copper bimetallic MOF material (FexCu1-x(BDC)) as a novel Fenton-like catalyst was prepared by a simple solvothermal method, and its performances were evaluated in the catalytic degradation of sulfamethoxazole (SMX) in the presence of hydrogen peroxide. The results indicated that the FexCu1-x(BDC)/H2O2 system was highly effective for SMX degradation over a wide pH range (4.0-8.6). At initial solution pH of 5.6, the bimetallic Fe0.75Cu0.25(BDC) catalyst exhibited a 100% SMX (20 mg L-1) removal within 120 min, which was superior to the SMX removal efficiency over monometallic Fe(BDC) and Cu(BDC) catalysts. Combined with the physical-chemical characterization, the synergistic effect between Fe and Cu species were responsible for the efficient catalytic activity. Moreover, the Fe0.75Cu0.25(BDC) catalyst showed good reusability for SMX degradation. The possible reaction mechanism in FexCu1-x(BDC)/H2O2 system was also tentatively proposed. This work has not only suggested the potential of bimetallic FexCu1-x(BDC) catalysts in Fenton-like treatment of antibiotics, but also provided useful information to develop MOF-based catalysts for efficient environmental remediation.