Synthesis And Catalytic Properities Of Water Oxidation Catalyst Immobilized On Functionalized MOFs

Metal-organic frameworks?MOFs?are a new class of porous materails formed by the sef-assembly of metal ions and organic linkers.They possess acceptable chemical stability,large specific surface area,porosity,tunable structure and properties.Recently,post-synthesis modification?PSM?has been investigated as a very important method to introduce functional groups into MOFs.Enhancing water oxidation capability plays an important role in artificial photosynthesis.Thus,in this thesis we developed a covalent-functionalization-assisted coordination strategy that could tandem post-synthetically modify the MOF linkers.Though this strategy a biomimetic di-?-oxo dimanganese complex bearing two triazole-binding tridentate ligands was successfully anchored inside a metal-organic framework?MOF?and the MnTD@MIL-101?Cr?-triazole was then obtained.Subsequently,we used a series of characterization methods to verify that the di-?-oxo dimanganese complex was constructed in the MIL-101?Cr?structure,and the results showed that the original framework structure and morphology of the modified MOFs were still retained with high a specific surface area.The thesis further studied the chemical oxygen evolution performance of MnTD@MIL-101?Cr?-triazole.Compared with MnTD,MnTD/MIL-101?Cr?and MnTD???MIL-101?Cr?,MnTD@MIL-101?Cr?-triazole showed significantly improved oxygen evolution efficiency as well as outstanding stability under harsh water oxidation conditions.Furthermore,we explored the water oxidation kinetics of the composite material and found that the reaction exhibited first-order kinetics characteristics of Mn and potassisum persulfate.In addition,the O₂ evolution terminated completely in the presence of p-benzoquinone,indicating a superoxide radical-involved mechanism.