Properties Of The Metal Coordination Polymers Based On Polycarboxylic Acid Ligands

Coordination polymer is made by metal ions or metal clusters with organic ligands through self-assembly. Over the past decade, functional metal-organic frameworks(MOFs) have attracted much attention, not only for their compositional and structural diversities, but also for their potential applications in the areas of catalysis, luminescence, gas adsorption and separation, ion exchange, magnetism and so on. As a result, the functional MOFs has become one of the hot topics in the field of coordination polymer. And the choice of organic ligand is very important to construct functional MOFs. A large number of studies have shown that carboxylic acid ligands are more easily to form the diverse coordination polymers because of their various coordination modes. Therefore, in this paper we use 2,3′,5,5′-biphenyl tetracarboxylic acid(H4L) with metal nitrates under the different solvent thermal conditions, successfully synthesized four metal-organic frameworks with new structures and various functions. These four coordination polymers were characterized by XRD, infrared spectra, thermogravimetric analysis, elemental analysis and so on, and we have further researched and discussed their potential properties. This paper will be divided into four parts:In the first chapter, we briefly introduced the MOFs and theirs application in various fields, and the significance and research progress of the selected topic.In the second chapter, under the solvent thermal conditions, we use 2,3′,5,5′-biphenyl tetracarboxylic acid ligand with transition metal cadmium nitrate, manganese nitrate and zinc nitrate to synthesize three kinds of coordination polymers Cd2(L)(DMF)2(H2O)2(1),Mn2(L)(DMF)2(H2O)2(2),[NH2(CH3)2]2[Zn7L4(DMF)2(H2O)3]·19H2O(3). Complex 1 and complex 2 are isomorphism, we also discussed the structure of the three kinds of coordination polymer. Complex 1 have showed potential applications in the field of catalysis and fluorescence, complex 2 showed excellent magnetic properties, while complex 3 has fluorescent property.In the third chapter, we introduced a coordination polymer [(CH3)2NH2] [In(L)]·CH3CH2OH(4), which was synthesized by 2,3′,5,5′-biphenyl tetracarboxylic acid ligand and indium nitrate under the solvent thermal condition. The coordination polymer features a 3D uninodal four-connected SRA topology with Schl?fli symbol of 42·63·8. And we also studied the fluorescence and absorption properties of complex 4.In the conclusion, we summarized the structure and the application in various field of the four metal-organic coordination polymers. The research provided a theoretical basis for design and synthesis of new functional metal-organic coordination polymers.