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本文利用Ｅｕ（Ⅲ）在有机萃取相中，５Ｄ０→７Ｆ２５Ｄ０→７Ｆ１两个跃迁的荧光峰高及比值作为研究Ｅｕ（Ⅲ）配位层组成和结构的探针。研究了ＴＢＰ，ＤＢＰ，Ｐ２０４与Ｐ５０７等４种有机磷萃取剂和Ｅｕ（ＣｌＯ４）３，Ｅｕ（ＮＯ３）３两种铕盐水溶液的萃取物的荧光光谱。发现萃取剂直接取代内配位层中水的能力不强，在萃取物中很可能形成外配位层，表现为荧光受到内层水分子的强烈猝灭。利用阴离子对Ｅｕ（Ⅲ）亲和力的差别，用ＮＯ３－先行取代或从有机萃取物中取代内层的水分子，可观测到荧光的明显增强，表明内配位层［组成与结构的变化。这一现象有可能用作改进萃取剂设计和萃取工艺时的参考。
In this paper, the fluorescence peak height and ratio of Eu (Ⅲ) in the organic extraction phase, 5D0 → 7F25D0 → 7F1 are used as probes to study the composition and structure of the Eu (Ⅲ) coordination layer. The fluorescence spectra of four organic phosphorus extractants (TBP, DBP, P204 and P507) and Eu (ClO4) 3 and Eu (NO3) 3 aqueous solutions were studied. It was found that the ability of the extractant to replace the water in the inner coordination layer is not strong, and it is likely that the outer coordination layer is formed in the extract, which manifests that the fluorescence is strongly quenched by the water molecules in the inner layer. Using the difference of the affinity of anions to Eu (Ⅲ), the obvious enhancement of fluorescence can be observed by substituting NO3-first substitution or replacing the inner water molecules in the organic extracts, indicating that the inner coordination layer [composition and structure changes. This phenomenon may be used as a reference for improving extractant design and extraction processes.