冠醚存在下稀土络合物荧光体系的荧光增强效应

Flurorescence Enhancement of Rare Earth Elements Under the Existence of Crown Ethers

本文详细研究了冠醚对Eu-TTA荧光体系的增敏作用和稀土离子Dy^(3+)或Ho^(3+)对Eu-TTA-冠醚体系的荧光增强效应。对Eu-TTA-冠醚和Eu-Dy(或Ho)-TTA-冠醚体系,Eu的浓度分别在1.0×10^(-8)～4.0×10^(-6)mol/L,1.0×10^(-9)～1.0×10^(-7)mol/L和1.0×10^(-8)～9.0×10^(-6)mol/L范围内与体系的荧光强度呈线性关系,检测限分别为1.0×10^(-10)mol/L,1.0×10^(-11)mol/L和1.0×10^(-10)mol/L。采用多点增量标准加入法测定混合稀土样品中痕量的Eu,获得了满意的结果。

In the luminescence system of Eu-thenoyltrifluoroacetone(TTA), we observed a new fluorescence enhancement phenomenon, which occurred by adding some of crowm ethers to above system. The fluorescence intensity of the system was increased about 580-fold by adding dibenzo-18-crown-6. The fluorescence intensity was a linear function of the concentration of europium in the range of 1.0× 10^(-8)-4.0× 10^(-6) mol/L. The detection limit was l.0×10^(10) mol/L. We also found that the fluorescence intensity of Eu-TTA-crown ether system was enhanced by adding Dy^(3+) or Ho^(3+). The fluorescence intensity was increased about 83 and 10-fold, respectively. The systems were used for the determintion of europium in rare earth samples with satisfactory results.