铕、铽四元配合物的合成及其发光性能

以对苯二甲酸(p-PA)、苯甲酸(BA)、邻(间、对)甲基苯甲酸o(m、p)-MBA]和1,10-邻菲啰啉(phen)为配体,合成了4种Eu(Ⅲ)和4种Tb(Ⅲ)的四元配合物。通过EDTA配位滴定分析和元素分析,确定了各配合物的组成。利用红外光谱分析对配合物的结构进行了初步表征,在配合物中羧基氧原子和1,10-邻菲啰啉中的氮原子均参与了配位。在室温条件下,测定了各固体配合物的激发和发射光谱,结果表明:4种铕的四元配合物中,苯甲酸配合物在614 nm最强发射峰的荧光强度强于3种甲基取代苯甲酸配合物的荧光强度;4种铽的四元配合物中,以对甲基苯甲酸为配体的配合物在545 nm最佳发射峰和490 nm次强发射峰的荧光强度较高。

Synthesis and Fluorscence of Quaternary Europium and Terbium Complexes with Aromatic Carboxylic Acid and 1,10-phenanthroline

Rare earth metal complexes have special characteristics, such as extremely narrow emission bands and high internal quantum efficiencies, which are suitable to be used as the emission materials. Eu(Ⅲ) complexes are a kind of good red luminescence materials and Tb(Ⅲ) complexes are a kind of good green luminescence materials. During the past decade, many ternary rare earth complexes have been reported, but quaternary rare earth complexes are seldom reported. In this article, eight quaternary complexes of Eu(Ⅲ) and Tb(Ш) have been synthesized with benzoic acid(BA), p-phthalic acid(p-PA), o(m,p)-methylbenzoic acid as the first ligand and the neutral phenanthroline as the second ligand. They were characte-rized by EDTA titration, elemental analysis and IR methods. Their compositions were: Eu2(p-PA)(BA)4-(phen)2·2H2O, Eu2(p-PA)(o-MBA)4(phen)2·2H2O, Eu2(p-PA)(m-MBA)4(phen)2·2H2O, Eu2(p-PA)(p-MBA)4(phen)2 ·H2O, Tb2(p-PA)(BA)4(phen)2·2H2O, Tb2(p-PA)(o-MBA)4(phen)2· 2H2O, Tb2(p-PA)(m-MBA)4(phen)2·2H2O and Tb2(p-PA)(p-MBA)4(phen)2·H2O, respectively. In these complexes, the metal ions were bonded to the oxygen atoms of carboxylate and the nitrogen atoms of phen. The excitation and luminescence spectra of the complexes were carried out at room temperature. Four kinds of Eu(Ⅲ) complexes emit intense red fluorescence under ultraviolet excitation. The intensity order of the strongest emission peak 5D0 →7F2(614 nm) for these Eu(Ⅲ) complexes were: Eu2(p-PA)(BA)4-(phen)2·2H2O＞Eu2(p-PA)(o-MBA)4(phen)2·2H2O>Eu2(p-PA)(p-MBA)4(phen)2·H2O＞Eu2(p-PA)(m-MBA)4(phen)2·2H2O. Four kinds of Tb(Ⅲ) complexes emit intense green fluorescence under ultraviolet light. The intensity order of the strongest emission peak 5D4→7F5 (545 nm) for these Tb(Ⅲ) complexes is: Tb2(p-PA)(p-MBA)4(phen)2·H2O＞Tb2(p-PA)(o-MBA)4(phen)2·2H2O＞Tb2(p-PA)(BA)4(phen)2·2H2O＞Tb2(p-PA)(m-MBA)4(phen)2·2H2O.