以对氯苯甲酸为第一配体, 2,4,6-三吡啶基三嗪(TPTZ)为第二配体,分别以铕、铽和镝为中心, 合成了10种稀土配合物, 并进行了元素分析、稀土络合滴定、等离子光谱、紫外光谱、红外光谱和发光光谱测定。配合物的组成为: RE(p-ClBA)3(TPTZ)·2H2O和RE0.5Ln0.5(p-ClBA)3(TPTZ)·2H2O(RE=Eu3+, Tb3+, Dy3+; Ln=La3+, Gd3+, Y3+; p-ClBA=对氯苯甲酸根; TPTZ=2,4,6-三吡啶基三嗪),均为非电解质; 对氯苯甲酸的羧基氧原子与稀土离子配位, 2,4,6-三吡啶基三嗪以主配位点上的3个氮原子与稀土离子配位; 铕配合物的发光强度大于铽配合物的, 镝配合物发光最弱; 在上述3种发光稀土配合物中分别掺入发光惰性稀土离子镧、钆及钇后, 发光强度有不同改变, 掺入镧可明显增强铕、铽的发光强度, 钆可敏化铕、铽和镝的发光, 而钇的敏化作用较弱。表明:掺杂配合物并不完全是两种简单配合物的机械混合, 而是有混配配合物生成。

In this work, ten complexes of europium, terbium and dysprosium with p-chroro-benzoic acid and 2,4,6-tris-(2-pyridyl)-s-triazine (TPTZ) were synthesized and characterized by elemental analysis, rare earth coordination titration and inductively coupled plasma atomic emission spectrometry (ICP), the results showed that the complexes have the composition of Eu(p-ClBA)3(TPTZ)·2H2O; Tb(p-ClBA)3 (TPTZ)·3H2O and Dy(p-ClBA)3(TPTZ)·2H2O; Eu0.5La0.5(p-ClBA)3(TPTZ)·2H2O, Eu0.5Gd0.5 (p-ClBA)3 (TPTZ)·2H2O, Eu0.5Y0.5(p-ClBA)3(TPTZ)·2H2O, Tb0.5La0.5(p-ClBA)3(TPTZ)·2H2O Tb0.5Gd0.5(p-ClBA)3-(TPTZ)·2H2O, Tb0.5Y0.5(p-ClBA)3(TPTZ)·2H2O and Dy0.5Gd0.5(p-ClBA)3(TPTZ)·2H2O. The molar conductivity indicated that all the complexes are non-electrolytes. The ligands and the complexes were studied by the means of IR spectra, UV spectra, fluorescence excitation and emission spectra. The results showed that p-chroro-benzoic acid is bonded with rare earth ions through oxygen atoms in the carboxyl group; 2,4,6-tris-(2-pyridyl)-s-triazine through the three nitrogen atoms coordinate with the rare earth ions. The red shift in UV absorption spectra of the complexes is observed, substantiating that a more extensive π-π* conjugating system is formed due to the coordinated reaction. The fluorescence emission intensity of Eu(p-ClBA)3(TPTZ)·2H2O is the strongest compare with other two rare earth complexes ［Tb(p-ClBA)3-(TPTZ)·3H2O and Dy(p-ClBA)3(TPTZ)·2H2O］. But, the fluorescence emission intensity of Tb0.5La0.5-(p-ClBA)3(TPTZ)·2H2O is the strongest in the doped rare earth complexes. The doped rare earth ions (La3+, Gd3+ and Y3+) can sensitize the luminescence of the complexes, it showed that a part of dinuclear complexes are formed.