Synthesis And Properties Of Metal-organic Frameworks Based On Polydentate Carboxylate Ligands

Metal-organic frameworks (MOFs), a magical class of crystalline materials, which were composed of metal ions and organic ligands, have presented outstanding potential application for separation and gas storage, heterogeneous catalysis, chemical sensing, controlled release, and drug delivery. Particular, the lanthanide (4f) complexes usually manifest intense emission. Therefore, Lanthanide-organic frameworks (LnOFs) have become a content-rich research field over the past decade due to their unique optical properties and extensive applications in many areas, such as luminescent devices, luminescence bioassays and fluorescent probes. Among the multifarious potential applications, the fluorescent probes of chemicals are the most promising one because of their operability, rapidity, high sensitivity and high selectivity. On account of the environmental pollution and homeland security, nitroaromatic explosives and heavy metal ions have drawn extensive attentions. Nitrobenzene (NB) is a vital component of nitroaromatic explosives and an infamous environmental contaminant, which can give rise to grisly health problems. The rapid and precise detection of NB is crucial to environmental protection and homeland security. Iron is a necessary element for the human body. Deficient iron will result in tissue damage or increase cardiovascular diseases. Excess iron is also an important pollutant owing to its high toxicity. Therefore, selective detection of Fe3+ with a lower detection limit is also of prime importance. In recent years, organic dyes have been widely used in industry, but leave in industrial wastes that causing serious environmental problems. Therefore, the adsorption and separation of organic dyes are important. This paper will be divided into four chapters:In the first chapter, we introduced the basic conception of coordination polymer, the application of the coordination polymers that based on V-shape carboxylate ligands and highly symmetrical tetra-carboxylate ligands.In the second chapter, three coordination polymers, [Tb(mtpc)1.5(DMA)(H2O)]·2H2O (1), [Dy(mtpc)1.5(DMA)(H2O)]·2H2O (2) and [Er(mtpc)1.5(DMA)(H2O)]·2H2O (3) have been successfully constructed based on V-shape rigid ligands [2’,4’-dimethyl]-1,1’:3’,1"-terphenyl,4,4"-dicarboxylic acid). Complexes 1,2,3 are isomorphous polyrotaxane lanthanide-organic frameworks. Complex 1 showed excellent fluorescent property.In the third chapter, two metal-organic coordination polymers, [Me2NH2][In(bptc)](DMF)(CH3CN)(H2O)4 (4). [Me2NH2][In(tptc)](DMF)2(H2O)4 (5) have been constructed by highly symmetrical tetra-carboxylate ligands 3,3’,5, 5’-Biphenyltetracarboxylic acid and [1,1’:4’,1"-Terphenyl]-3,3",5, 5"-tetracarboxylic acid and Indium metal ions under different solvothermal conditions. Complex 5 showed wonderful selectively absorption and separation properties.In the conclusion, we have summarized the structures of the five metal-organic coordination polymers. Our work demonstrated that metal-organic frameworks could be excellent candidates for luminescent molecular probes, switches, sensors and adsorbent under realistic conditions in the near future.