Preparation And Fluorescence Properties Of Europium (III) Complexes

Rare earth luminescent material include photoluminescence, cathodeluminescence, X-rayluminescence and electroluminescence material et al. Have great application value in laser, photoluminescence and electroluminescence compound domain et al. In this paper, we study the synergetic effects of second ligand and luminescence enhancement effects of doping ions starting from the binary complexes of europium with inexpensive benzoic acid and its derivatives, and improve the luminescence of compounds step by step. The main work is divided into three parts:1. Series of binary and ternary complexes of europium with benzoic acid , p-aminobenzoic acid,p- Nitrobenzoic acid,phthalic acid and w-phthalic acid were synthesized and characterized by IR, UV, XRD and Fluorescence Spectra, The fluorescence intensity and enhancement factor analysis of various series complexes were stressed and its fluorescence enhancement effect compared. We found: the joining of second ligand had obvious synergism effect in enhancing the luminescence intensity of Europium ion.2. Series of ternary and quadruple doping complexes of europium with benzoic acid ,p-aminobenzoic acid,phthalic acid , m-phthalic acid (first ligand ), and 1,10-phenanthroline (second ligand) were synthesized. Experiment results found that non-fluorescence inert ion had relative good fluorescence enhancement effect to complexes, but its performance was worse than second ligand Fluorescence enhancement factor 6 was introduced. By 6's value, we could know the effect of mol fraction of doping non-fluorescence inert ions to complexes' fluorescence intensity and the its fluorescence intensity varying when doping various ions, thereby found its varying law: within 0.1 and 0.9 ,the higher the doping ions' mol fraction was, the better the complexes' fluorescence enhancement effect was. The basic order of fluorescence enhancement was3. At the last, this paper analysed the energy transfer mechanism of doping complexes, and thought that the energy transfer of doping inert ions to luminescent center Eu3+ finished through fragrant clan carboxylic acid ligand by means of didentful or μ2 complexes with Eu3+, namely formed iso-binuclear or iso-multinuclear structure, as a result its fluorescence intensity enhanced.