Synthesis And Performance Study Of Metal-organic Framework Based On Tetrastyrene Skeleton

Metal-organic frameworks?MOFs?are periodic network structures formed by self-assembly of metal ions and organic ligands.As new multifunctional crystalline materials,MOFs combine the advantages of inorganic and organic materia ls,and synergistically produce new structural and property characteristics.MOFs have the advantages of multiple porosity,high specific surface area,multiple active sites,and structural tunability.They are widely used in the fields of gas storage and separation,luminescent properties,chemical sensing,magnetism,and biomedicine.In this paper,nitrogen heterocyclic organic ligand 1,1,2,2-tetrakis?4-?imidazol-4-yl?phenyl?ethylene?TIPE?was synthesized,and a several metal-organic frameworks were synthesized by hydrothermal method.And their performance were characterized and tested.The specific content is divided into the following three sections:Two three-dimensional self-interpenetrating or interpenetrating metal-organic frameworkmaterials{[Cd₄?L?₂?oba?₄]·4H₂O}n?1?and{[Co₄?L?₂?BPDC?₄·4H₂O]·5MeCN·5H₂O}n?2?,?L=TIPE?self-assembled with TIPE,metal salts and diacid ligands under hydrothermal conditions.Thermogravimetric analysis shows that the complexes have good thermal stability.Fluorescence analysis certified that 1 has high selectivity and sensitivity fluorescence quenching response for TNP and Fe³⁺,but complex 2 havs high selectivity fluorescence quenching response for TNP only.Two 3D MOFs were prepared by ligands TIPE and CuX?X=Cl,Br?,namely{[ClCu₄?L?₃]·4Cl}n?3?and{[BrCu₄?L?₃]·2Br·2Cl}n?4?,?L=TIPE?.Structural analysis shows that they have the same three-dimensional gfy structure and Cu?I?metal sites.The catalytic ability of 3 and 4 for terminal phenylacetylene and benzyl azide was investigated,and it was found that the yields can reach 99%under the condition of 70?C used water as solvent.Two new MOFs were obtained based on the ligand TIPE and metal salts,{[Ag₄?L?₃O]·2H₂O}_n?5?and{[N i₄L?L₁?₂·2H₂O]}_n?6??L=TIPE;L₁=4,4'-Stilbenedicarboxylic acid?.Complex 5 is composed of TIPE-connected secondary unit structure(O^2-and four Ag⁺coordination formation).Complex 6 has a large cavity with a size of 42.454×37.924?².Preliminary studies have shown that 5 have a highly selective and sensitive fluorescence response to TNP,2-NA,DNA?TNP=2,4,6-trinitrophenol;2-NA=2-nitroaniline;DNA=2,4-dinitroaniline?.