Studies On The Rare Earth Complexes Composite Luminescent Materials Of SiO₂/Polymer Matrices

In the 1970's, material was listed as one of the three major pillars of the modern civilization, Since 1980s, it became an important symbol of the new technological revolution, which shows its importance, universality and diversity. In order to improve the performance of rare earth complexes in recent years, research staffs mainly use inorganic matrix structure and some of the inherent physical properties of rare earth to get the optimized luminescent material. The photophysical properties, the light and heat stability of the rare earth complexes composite materials using the SiO2/organic polymer matrices assembled by sol-gel method were significantly improved compared with complexes. Composite host-guest supramolecular interactions between the substrate, the porous composite structure and properties of the object matrix and the dispersion of rare earth complexes, polymer dispersion of rare earth complexes, isolation and protection of its not being-OH The role of quenching the composite material make the luminescent behaviors and stabilities significantly improve.The thesis is divided into three parts:1. A number of rare earth complexes with carboxylic acid type podands and SiO2/organic polymer matrices composite materials are briefly reviewed.2. Five binary or ternary rare earth complexes with two new carboxylic acid type podands H2L1 and H2L2 are synthesized and characterized by the elemental analysis,1H NMR, infrared spectroscopy and X-ray single crystal diffraction. The results show that the same rare earth ligand binary complexes have similar structures; different ternary complexes with ligands possess different structures. Ternary complex crystal structure analysis shows that in the complex, the carboxylate ligands have two coordination modes, each of the second ligand are associated with a rare-earth ions, the second ligand crowd out water molecules, which affect the luminescence behavior of rare earth ions.3. The rare earth complex composite luminescent materials using the synthesized complexes as the active center and SiO2/polymer as the hybrid matrices have been assembled through the sol-gel method. And the microstructures of the materials have been characterized by infrared spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) means. On this basis, the photopyhsical behaviors, photostabilities of the composites, the complex matrix microenvironment and molecular interactions between the rare earth ions and the matrices have studied and discussed in detail. The results show that the composite materials have good optical properties, including significant improvement of the luminescence intensity, lifetime and the light and heat stability compared with the complexes. The host-guest interactions between SiO2/polymer matrices and the rare earth complexes, porous network structures of rare earth complexes, the main matrix properties of the dispersion of the complex, the role of organic polymers and the coordination rare earth complexes isolation and protection of the luminescence quenching by the vibration of -OH groups, have made the photophysical properties of the composite materials improve significantly.