Studies On The Rare Earth Complexes With β-Diketone Ligand And Their Composite Luminescent Materials

β-Diketone rare earth complexes have always attracted many attentions in coordination chemistry and rare earth luminescent materials. And it is demonstrated that the complexes may be widely applied in analytic chemistry, medicine, life science, fluorescent probe and luminescent devices for their special luminescence mechanism and good luminescent properties. But their applications are limited by the poor optical, thermal and chemical stabilities. Stable inorganic solid matrices which can change the structure and chemical microenvironment of guest molecules or ions, could affect the luminescent properties of guest molecules or ions distinctly. So the hybrid of the rare earth organic complexes with suitable inorganic solid matrices is a desirable way to improve the luminescent properties and the stabilities of the complexes, develop novel rare earth luminescent materials and widen their application field. Till now the works are mainly concentrated on single inorganic matrix such as SiO₂ gels, But conventional gels tend to crack during the drying period owing to their poor mechanical strength. One strategy is to introduce polymer or organic into inorganic matrix and the obtained polymer/inorganic hybrids exhibit notable mechanical strength and optical properties. We intermingleβ-diketone rare earth luminescent complexes into a sol-gel derived PVB/SiO₂ matrix and obtain novel rare earthβ-diketone complex-PVB/SiO₂ matrix composite luminescent materials.This dissertation including following four parts:1. A brief review on the research developments of theβ-Diketone complexes and the rare earth complex-inorganic matrices composite luminescent materials prepared by sol-gel method.2. Theβ-diketone ligands L^I-L^VI and six series of their complexes of rare earth nitrate were synthesized and characterized by elemental analysis, molar conductance, ¹HNMR, IR spectra, electronic spectra and X-ray crystal structure analysis. The results show that these ligands can form stable complexes with rare earth nitrate and coordination with the central ions in enol structure. Moreover, the compositions and structures of the complexes can be affected remarkably by the substitution groups of the ligands.3. The luminescent properties of the above complexes were investigated. The results indicate that the different substitutionl groups, the structure of complexes and the solvents can influence the luminescent properties of the complexes. The triplet state energy levels of the ligands match better to the resonance levels of Tb (III) than to Eu (III). 4. Above mentioned complexes were intermingled into the PVB/SiO₂ matrices by sol-gel method. The results show that the obtained composite luminescent materials have better luminescent properties and stabilities than those of the corresponding rare earth complexes. We deduce that this result comes from the effects of the supramolecular interaction between the host matrix and the guest complexes, the porous network structure of the assemblies and dispersive, isolation and protection action of the matrices. Moreover, the substitution groups and the intermingle quantity of the complexes can also affect the luminescent properties of the composite materials to a certain extent.