Syntheses,Structures And Properties Of Rare Earth Coordination Polymers Based On Imidazophenanthroline Ligands

Coordination polymers have been widely used during the past few years because of their diversified bonding modes,fantastic space configurations and unique physical properties.Especially many coordination polymers show unique functions in the fields such as optical,magnetic,biological and electrical,which makes it become a kind of functional complexes with practical significance.Based on functional complexes,it can be assembled into molecular materials and nanomaterials with richer physical properties and lay the foundation for aggregated nanomaterials molecular devices and molecular machines.The thesis is aimed at constructing lanthanide coordination polymers which possess favorable thermostability,sensing and luminescence.The thirty lanthanide coordination polymers are successfully designed and synthesized by the reactions of bifunctional imidazophenanthroline derivative ligands with rare earth metal ions(La?-Yb?,Y?).Through X-ray analytical each class was described in detail the structure of the complexes,and through IR,element analysis for further characterization was carried out,through the powder diffraction to determine the purity of complexes.The thermal stability and fluorescence properties of each polymer were investigated,as well as sensing properties of a certain compound.The text is divided into the following three chapters:Chapter 1:Mainly summarized the research significance of rare earth metal coordination polymers,the coordination characteristics of rare earth metal ions and the optical properties of lanthanide coordination polymers.Reviews on the research progress of rare earth metal coordination polymers based on imidazophenanthroline ligand.Finally,the selected topic basis and research significance of this paper were elaborated.Chapter 2:Four types,seventeen rare earth coordination polymers(1-17)based on H3sfpip and oxalic acid,succinic acid,adipic acid as auxiliary ligands were synthesized.The structures of the coordination polymers were depicted in detail and the effects of auxiliary ligands and reaction conditions on constructing polymers were discussed.The fluorescence and thermostability properties of 1-17 were researched.Results indicate that H3sfpip can absorb energy efficiently and sensitization Eu? and Tb?.Sensing study reveal that 15 as luminescence sensor for detecting NB possesses the characteristic of high selectivity,high sensitivity,good reproducibility ability and the fluorescence response signals can be distinguished by naked eye under 365nm UV light irradiation.The quenching mechanism have been discussed in the end.Chapter 3:Three types,thirteen rare earth coordination polymers(18-30)based on HL and adipic acid as auxiliary ligands have been successfully synthesized by changing the stoichiometric ratio and pH value of the reactants.The structures of the coordination polymers were depicted in detail and the effects of reaction conditions on constructing polymers were discussed.The properties of 18-30 were also researched,and the results indicate that 18-30 have excellent luminescence properties and thermal stabilities.In addition,white light emission was realized by precisely tuning the mixing molar ratio of Eu?/Tb? compounds and change the excitation wavelength.