Constructing Bimetallic Cobalt-Iron MOF-derived Carbon for Efficiently Activating Peroxydisulfate to Improve Degradation of Organic Pollutants

Peroxydisulfate activation has garnered a lot of interest due to its benefits of broad adaptability, strong anti-interference ability, and powerful oxidation capacity. Due to their low cost and potent action, carbon materials are new green catalysts that have garnered interest. In order to effectively degrade organic contaminants in water by activating peroxydisulfate, carbon compounds are currently commonly used. Better metal ions for activating peroxydisulfate include Fe2+ and Co2+, and these metal ions can be encapsulated in carbon compounds made by calcinating metal organic framework（MOFs ）as precursors. The synthesis of carbon compounds from MOF precursors as well as their effectiveness and mechanism in reducing organic pollutants in peroxydisulfate systems. The following are the specific research contents: NH2-MIL-101 (Fe/Co) bimetallic MOFs material was synthesized by hydrothermally altering the Fe3+ to Co2+ ratio, followed by the carbonization of Fe/Co-CNs. XRD, SEM, TEM, FT-IR, and XPS were used to analyze the materials' morphology, structure, and chemical make-up. The results demonstrate that Fe/Co-CNs-2 (Co2+ doping concentration approaches 20%) has a stable three-dimensional carbon structure and effectively incorporated Co ions into the carbon material. The simultaneous encapsulation of both Fe and Co metals by the three-dimensional carbon skeleton ensures material stability and reaction activity. Tetracycline hydrochloride was reported to degrade more quickly in Fe/Co-CNs-2 than in other Co2+ doping concentrations within 30 minutes of peroxymonosulfate（PMS） activation. The degradation rate of Fe/Co-CNs-2 for 20 mg/L TC was determined to be 93.34% within 30 minutes under the following conditions: Fe/Co-CNs-2 concentration of 0.1 g/L, PMS concentration of 0.2 g/L, and pH of 7.33. The catalyst also demonstrates good stability. Last but not least, the Fe/Co-CNs-2 free radical quenching experiment revealed that singlet oxygen (1O2) is the primary active species in the reaction system, and a potential mechanism was examined by combining degradation and XPS analysis.