| The study of rare earth complexes luminescence, being the cross science of inorganic materials luminescence, organic materials luminescence and organism luminescence, is very important for fundamental and applied research. Rare earth complexes have become excellent luminescence materials, this is related to lanthanide ions' peculiar characteristics. And have potential use in laser, photoluminescence and electroluminescence. In this paper, we study the synergetic effects of second ligands and luminescence enhancement effects of doping ions starting from the binary complexes of europium and terbium with inexpensive benzoic acid and its derivatives, and improve the luminescence of complexes step by step. The main work is divided into four parts:1. The binary complexes of europium and terbium with benzoic acid and its derivatives (phthalic acid, m-phthalic acid, o-aminobenzoic acid, salicylic acid, sulfosalicylic acid) were Synthesized and their fluorescence properties compared .The IR spectra showed that the IR spectra of complexes are different from those of free ligands. The fluorescence properties of them were investigated by using luminescence spectroscopy, the results showed that all the six complexes of terbium exhibited excellent luminescence, and the complexes of terbium with sulfosalicylic acid had the strongest fluorescence intensity, and was stronger than o-aminobenzoic acid-terbium, whose fluorescence intensity was regarded as the strongest one in the literature, and even stronger than some phosphor of terbium. To europium ion, their fluorescence properties of its complexes with these ligands were inferior to corresponding terbium complexes, only three complexes show better luminescence, they were Eu-benzoic acid Eu-m-phthalic acid and Eu-phthalic acid, while the others exhibited the ligands' wideband emission.Micro-wave solid synthesis method was applied in synthesizing Tb-sulfosalicylic acid for the first time. The results of IR and XRD manifest that the products of microwave solid synthesis method and precipicitation method have the same coordination and crystal structure.Synthesis and fluorescence properties of solid Tb-sulfosalicylic acid were not reported in the literature.2. The ternary complexes of europium and terbium were synthesized and characterized by UV, IR and Fluorescence Spectra. In the binary complexes of europium, the introduction of the second ligands, 1,10-phenanthroline, 1,10-phenanthroline-N-oxide, 2,2-bipyridine,diantipyryl methane, trioctylphosphine oxide, could improve the fluorescence intensity greatly.In the binary complexes of tebium, the introduction of the second ligands, 2,2-bipyridine,diantipyryl methane, trioctylphosphine oxide, could can improve the fluorescence intensity to some extent, while the introduction of 1,10-phenanthroline, just reduced the fluorescence intensity, ie, the fluorescence intensity of the ternary complexes was inferior to that of binary complexes.The concept of negative synergistic effect of the second ligand and the mechanism of intra-molecule energy transfer of ternary complexes was firstly put forward, which accounted for why the introduction of 1,10-phenanthroline reduced the fluorescence intensity of ternary complexes of terbium(the negative synergistic effect of the second ligand) and improved the fluorescence intensity of ternary complexes of europium(the positive synergistic effect of the second ligand).3. A series of doped complexes of Eu-methacrylic acid-Phen , europium-TTA-Phen, Tb- o-aminobenzoic acid and Tb- sulfosalicylic acid four systems were synthesized and characterized by IR, XRD and Fluorescence Spectra.(l)The doped system of Eu-methacrylic acid-Phen. The effects on fluorescence properties of complexes of three doping ions(Gd3+, La3+ and Y3+) and their mole fraction were investigated and compared. For fluorescence intensity ,when x Gd was 0.9, x La was 0.9, x Y was 0.4, the corresponding doped complexes was the strongest in their respective series complexes.(2...
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