Preparation And Properties Of Rare Earth Hybrid Luminescent Materials

Because lanthanide ions always exhibit their unique luminescent properties, are widely used in optical, electrical and magnetic fields, but its stabilities is very poor, limiting its development. If rare earth compounds and other substrates with a variety of ways to prepare hybrid materials. The materials not only retain good luminescent properties of rare earth ions and various physical and chemical properties of other substrates, but also can complement the performance, give full play to the advantages of each component. In this paper, the main research work is divided into two parts:In the first part, A kind of functional bridge intermediate was prepared by modifying 5-Bromosalicylic acid with 3-(triethoxysilyl)-propylisocyanate through the hydrogen transfer nucleophilic addition. Subsequently, using the carboxylic group coordinated to lanthanide ion, the luminescent lanthanide molecular-based hybrids have been constructed from the sol-gel process with both molecular bridge and tetraethyl orthosilicate.1HNMR, FT-IR, UV, TG, SEM and luminescence spectra were applied to characterize the photophysical properties of the obtained hybrid material. As a result, lanthanide luminescent molecular-based organic-inorganic hybrid materials verify their unique luminescence properties and thermal stabilities, a homogeneous hybrid material system forms and no phase separation can be observed.In the second part, MCM-41 mesoporous silica has been functionalized with 5-Bromosalicylic acid, thisosalicylic acid and 3-Hydroxy-2-naphthoic acid through co-condensation approach of tetraethoxysilane in the presence of thecetyltrimethylammonium bromide surfactant as template. These ligand grafted to the coupling agent 3-(triethoxysilyl)propyl isocyanate (TEPIC) was used as the precursor for the preparation of mesoporous materials. Novel organic-inorganic mesoporous luminescent hybrid containing Ln3+(Eu3+, Tb3+) complexes covalently attached to the functionalized ordered mesoporous MCM-41, were obtained by sol-gel process. Subsequently,1HNMR, FT-IR, ultraviolet absorption, small-angle X-ray diffraction, nitrogen adsorption/desorption isotherms, and luminescence spectra were applied to characterize the photophysical properties of the obtained hybrid mesoporous materials. As a result, the above spectroscopic data present their unique luminescence properties and mesoporous materials have high surface area, uniformity in the mesopore structure and good crystallinity.