Build And Physical Properties Of Lanthanide Complexes Of Aromatic Dicarboxylic Acid Regulation

The development and research on the unique luminescent properties of lanthanide organic compounds enriched the luminescent material’s application, and had became the focus of the inorganic, organic and biological luminescence researches. Based on lanthanide compounds constructed by the phenanthrene aromatic carboxylic acid containing larger conjugate system and lanthanide, this thesis, starting with the second ligand, analyzes the synergy effect of the second ligand influence on structure and the luminescent properties of lanthanide compounds. The main contents and conclusions are as follows:The first part:The paper obtains the target products2-(4-carboxyphenyl) imidazo (4,5-f)(1,10)-phenanthroline (HNCP) by improving the methods of literature, which are characterized by elemental analysis (EA), electrons pray ionization mass spectrometry (ESI-MS), infrared spectroscopy (IR), H-nuclear magnetic resonance (’H NMR) and single-crystal X-ray diffraction.The second part: Based on the ligand HNCP and three kinds of lanthanide ions Eu(III)/Gd(III)/Tb(III), we introduce the second ligands benzene-1,4-dicarboxylic acid (1,4-H2bdc),4,4’-biphenyldicarboxylic acid (4,4’-H2bpdc),2,5-dibromoterephthalic acid (2,5-H2Br2bdc), and naphthalene-1,4-dicarboxylic acid (H2ndc), and synthesize four types of the twelve compounds1-12by the hydrothermal method:[Ln(NCP)(1,4-bdc)]n (Ln=Eu1, Gd2, Tb3),[Ln(NCP)(2,5-Br2bdc)],,(Ln=Eu4, Gd5, Tb6),[Eu(NCP)(4,4’-bpdc)],,(Ln=Eu7, Gd8, Tb9),[Ln(NCP)(ndc)],,(Ln=Eu10, Gd11, Tb12). Structural analysis, thermal analysis and photoluminescence spectroscopy also are conducted in this thesis. Structure analyses reveal that all of the compounds have binuclear3D super-molecular structure for the rich coordination model and strong coordination ability in carboxyl group. The thermal analyses show that all compounds possess a higher stability except for compound5and6which contain the free water molecules. Optical performance analysis results present that the HNCP has strong ability in absorbing light and is an excellent sensitizing agent, and the degree of sensitization of Eu (Ⅲ) ion is better than that of Tb (Ⅲ) ions.The third part:By comparing the luminescence performances (fluorescence intensity, fluorescence life and fluorescence efficiency) of Eu (Ⅲ) and Tb (Ⅲ) compounds, we find out how the second ligands affect glow lanthanide compounds in optical performances. The results show that the electron-withdrawing groups and water molecules, etc from system would have badly effect on the luminescence performance of compounds. Meanwhile, the fluorescence intensity increases with the conjugacy of second ligands, and the fluorescence life and fluorescence efficiency will also increase, in order,10﹥7﹥1﹥4,12﹥9﹥3﹥6.