取代基影响邻菲罗啉衍生物-铕能量传递和荧光性能研究

配体结构调控是提高稀土配合物发光强度的有效手段,根据稀土配合物发光原理,理想配体应具备较高的光捕获能力并且能有效地向稀土离子传递能量。研究表明,增加配体的共轭程度可使配体的光吸收能力增强,而不同电子给予特性基团的引入则会改变配体与稀土离子间的能级匹配程度,从而影响配体向稀土离子的有效能量传递,提高配合物的发光效率。本文以引入不同特性(共轭特性、电子给予特性)取代基的邻菲罗啉为配体合成6种铕的配合物,通过分析配合物的吸收光谱、红外光谱、荧光光谱和X射线光电子能谱等发现,供电子基团和共轭基团能够提高配体的电子云密度,增大配体的摩尔吸收系数,同时有利于配体与稀土离子间形成配位键,能够明显提高配合物分子内能量传递,并使配合物发光性能增强。

Substituent Effect of Phenanthroline Derivatives-Europium Complexes on Energy Transfer and Fluorescence Properties

Regulating the ligand structure is an effective method to improve the luminous intensity of the rare earth complexes.According to the luminescent principle of rare earth complexes,the ideal ligands should have higher ability to capture light and can transfer energy to rare earth ions effectively.Research shows that increasing the conjugation extent of ligands can enhance its light absorption ability,and the introduction of electron donating groups will change the energy-match between rare earth ions and ligand,which effect the effective energy transfer from ligands to rare earth ions and increase the of luminous efficiency.In this work,we used phenanthroline with different substituents(conjugated group and electron donating groups)as ligands to synthesize six europium complexes.Through the analysis of the absorption spectra,the IR spectra,fluorescence spectroscopy and X-ray photoelectron spectroscopy,we found that the electron donating groups and conjugated group could improve the electron density and the molar absorption coefficient of ligands,w hich is conducive to the formation of coordination bond between rare earth ions and ligands,improving the intramolecular energy transfer,so the luminescent properties of complexes is increased.