摘要
本文应用稳态和瞬态光谱技术探讨了稀土离子铽与水杨酸甲酯,苯酯所形成络合物的发光特性,它们向铕离子的能量传递过程;以及pH值对络合物的发光和能量传递的影响。络合物的发光比络合前铽离子的发光增强了几至十几倍;介质的pH变化影响到络合物的发光强度和能量传递效率,中性介质(pH:6～8)下的量传递效率最高。
The formation and luminescence properties of the complex of terbium ion (Tb3 + )-salicylates ( methyl salicylate MS, and phenyl salicylate PS) and the energy transfer processes from the complex to europium ion (Eu3 + ) have been investigated by use of the steady state and transient state time-resolved emission spectroscopy.From the fluorecence spectra and lifetime data of the MP system (Table 1), it can be seen that, with the increase of Tb3 + concentration, the fluorescence intensity of the MP decreases and the characteristic emission of Tb3 + ions increases.Plots of F0/F against the concentration of Tb3+ ions satisfy the Stern-Volmer equation.But the fluorescence lifetime remains constant, T0/=1. this is a typical static quenching process. Absorption changes are also observed in the absorption spectra and the absorption peaks of complex appear at longer wavelength than those of MS and PS do.We can conclude from the study that Tb3+ ions form steady complex in ground state with MP, MS by certain proportion and transfer the absorption energy effectively to center Tb3+ ions. The terbium luminescence intensity is increased by many times in the complex than that in the studied systems.The fluorescence spectra of the complex show that the fluorescence intensity decreases with the increase of the concentration of Eu3 + .From the transient time-resolved spectroscopy, the energy transfer process from the complex to Eu3 + ions may follow the scheme as. Moreover, the influn.ce of pH value on the luminescence and the energy transfer were investigated also.The dramatic variation of the energy transfer efficiency with the pH value was given and the highest efficiency was obtained in neutral medium(pH6-8).
出处
《发光学报》
EI
CAS
CSCD
北大核心
1989年第4期325-331,共7页
Chinese Journal of Luminescence
