| The lanthanide coordination polymers?Ln-CP? or metal-organic frameworks?Ln-MOFs? constructed from lanthanide ions and organic linkers with regular and multi-dimentional structures have attracted much attention due to their varied applications in the field of gas sorption and separation, chemical sensors, catalysis and so on. The rational selection of organic ligands is one of key factors to obtain functional Ln-MOF with specific structure and functionality. The aromatic carboxylic acid with strong coordination ability of carboxylate group and rigid aromatic rings can be used to assemble stable Ln-MOF. Meanwhile, the sulfonyle group has weaker coordination ability with oxygen atoms can partially or competely coordinate to the central metal ions. Thus the sulfonyl groups lined at the channles can tune the chemical and physical properties of the pore surface in the MOF, which may further influence the physical properties of the MOF, such as sorption and proton conduction properties. In this thesis, an aromatic carboxylic acid ligand containing sulfonyle group, biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic?H4-BPDSDC?, has been synthesized,which is used to construct functional Ln-MOF. Nine MOFs, namely,{[KLn?BPDSDC??DMF??H2O?]·x?solvent?}n?Ln = Pr?1?, Sm?2?, Eu?3?, and Gd?4??,[TbK?BPDSDC??H2O?2?DMF?]n?5?, {[Eu2?BPDSDC?1.5?H2O?4-?DMF?2]·x?DMF?}n?6?, and {[Ln K?BPDSDC??H2O?4]·2?H2O?}n?Ln = Er?7?,Yb?8?,and Dy?9???DMF' = N,N'-dimethylformamide?, have been synthesized.The thesis contains three chapters:The first chapter briefly introduces the properties and applications of the lanthanide MOFs.The second chapter introduces the synthesis and characterization of the biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic acid?H4-BPDSDC? ligand. Nine novel lanthanide-biphenyl-3,3'-disulfonyl-4,4'-dicarboxylic frameworks have been obtained and structurally characterized. The four isomorphous lanthanide compounds 1–4feature three-dimensional?3D? frameworks constructed from the one-dimensional?1D? rod-shaped heterometallic Ln-K secondary building units and are an illustration of a Kagome-like lattice with large 1D hexagonal channels and small 1D triangular channels. The selected compound 2 with porous character has an affinity to quadrupolar molecules such as C2H2 and CO2. In addition, compound 2 exhibitshumidity- and temperature- dependent proton conductivity with a large value of 1.11× 10-3 S cm-1 at 80 °C and 98% RH. The hydrophilic sulfonate group on the surface of channels facilitates enrichment of the solvate water molecules in the channels, which enhances the proton conductivity of this material. Moreover, the europium analogue 3can effectively and sensitively recognize of K+ with and Fe3+ ions in DMF solvent.The enhancing the Eu3+ luminescence with the K+ ion and quenching the Eu3+luminescence with the Fe3+ ion can be associated with the functional groups of the organic ligand. In compound 5, the carboxylate and sulfonate groups linked the Tb3+and K+ into a two-dimentional?2D? hetero-metal inorganic layer, which is further connected by the biphenyl skeleton of the BPDSDC4- anions into a 3D structure.Compound 5 can effectively recognize of Cr3+ ion. Compound 6 is a 2D structure based on the linear tetranuclear Eu4 units and displays Eu3+ luminescence. The isomorphous compounds 7–9 have 2D double layered structures. Finally, the luminescence properties of compounds 6?7 and 9 and the gas sorption properties of 7have been investigated.The third chapter summarizes the work of this thesis. |
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