Syntheses, Structures And Properties Of Lanthanide Coordination Polymers Constructed By 2,2’-bipyridine-6,6’-dicarboxylic Acid

Recently, metatorganic frameworks (MOFs) have attracted more and more attention due to not only their intriguing architectures but also their potential applications in luminescent materials, magnetism, microporosity and gas adsorption, ion exchange, and catalysis etc. Rare earth complexes have become excellent luminescence materials, this is related to lanthanide ions’ peculiar characteristics. In this paper, twenty-four lanthanide-metal MOFs based on 2,2’-bipyridyl-6,6’-dicarboxylic acid are designed and constructed successfully. These MOFs are characterized by single-crystal X-ray diffraction analysis, elemental analysis, IR spectroscopy and thermogravimetric analysis. This paper includes the following four chapters:Chapter 1:Fristly, the basic concept of metal organic coordination polymers and the synthetic methods are briefly summarized. The mechanism, species and affecting factors of fluorescence for lanthanide metal organic complexes are depicted. Secondly, Reviews on research development of bipyridyldicarboxylate complexes. Finally, The selected topic significance and research results of the article are introduced.Chapter 2:Complexes 1-13 are obtained as single phases by regulating the different pH values under hydrothermal conditions. The results indicate that pH values of a reaction system represent one the important factor in the self-assembly process of the metal-organic coordination polymer. The structure, fluorescent properties and thermal stability of the complexes are studied, and magnetic properties of 1-5 are discussed.Chapter 3:In order to obtain structure variety of complexes, complex 14,15 are synthetic in room temperature evaporation method. The structure, fluorescent properties and thermal stability of the complexes are studied.Chapter 4:Complexes 16-24 are obtained by choosing aliphatic oxalic acid and succinic acid as auxiliary ligands. Because of their flexibility, aliphatic oxalic acid and succinic acid act as a linear linker and coordinated with Ln ions through their carboxyl oxygen atoms. In addition, effects of the auxiliary ligand on the structures and the photo luminescence properties of the complexes are studied in the solid state at room temperature.