Preparation And Properties Of Luminescent Materials Through Carboxylic Europium(Terbium)Complexes Intercalating Into Montmorillonite

This paper was divided into two parts:synthesis and the luminescent properties of carboxylic europium and terbium photoluminescent complexes, the complexes above were intercalated to the interlayer of montmorillonite to prepare rare earth-montmorillonite composite materials.A series of carboxylic lanthanide complexes were synthesized by using rare earth nitrate, various aromatic acids (p-tert-butyl benzoic acid, p-methoxy benzoic acid, benzoic acid, etc.) and fatty acids (n-hexanoic acid, n-octanoic acid) as raw materials via saponification method. The influences of the doped fluorescent inert ion and the second ligands on fluorescent properties of complexes were explored. The results showed that the effective energy transfer from ligand to central ion made the complexes allowing characteristic fluorescence emissions of rare earth ions. The doped inert fluorescent ions and the change of ligands would affect the fluorescence intensity of complexes.The laminate structure of montmorillonite which belongs to inorganic layer silicate clay can provide a stable environment for carboxylic lanthanide complexes to overcome the poor light and thermal stability to realize better luminescent properties. Based on this study, the rare earth montmorillonite luminescent materials were prepared through a convenient method.Under UV excitation, the montmorillonite showed blue emission and the carboxylic europium (Ⅲ) and carboxylic terbium (Ⅲ) showed red and green emission respectively. The white, red and green montmorillonite luminescent materials could be prepared by controlling the ratio of the carboxylic lanthanide complexes intercalating to montmorillonite. Steady-state and transient fluorescence spectroscopy (FS), thermal gravimetric analysis (TG), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the montmorillonite luminescent materials. The results showed that carboxylic lanthanide complexes had been intercalated into the montmorillonite layer and realized excellent photoluminescence performance and greatly reduced the costs of novel and practical rare earth-montmorillonite luminescent materials.