化学学报 ›› 1996, Vol. 54 ›› Issue (5): 468-474. 上一篇    下一篇

研究论文

MMgF4(M=Ca, Sr, Ba)体系中Eu和Tb的电荷迁移

吴郢;石春山   

  1. 中国科学院长春应用化学研究所;中国科学院稀土化学与物理开放实验室
  • 发布日期:1996-05-15

Electron transfer between Eu and Tb in MMgF4 systems

WU YING;SHI CHUNSHAN   

  • Published:1996-05-15

于不同气流中, 合成了MMgF4:xEu,yTb复合氟化物磷光体。该体系中Eu^3^+和Eu^2^+共存。Tb的存在影响Eu的价态存在形式。ESR测试表明, 随Tb的掺入浓度增加, Eu^2^+的浓度呈规律性变化。随Eu的掺入, 样品的XPS谱中出现了四价铽的Tb3d5/2特征伴峰。认为Eu^3^+和Tb^3^+之间存在电荷迁移平衡。即Eu^3^++Tb^3^+=Eu^2^++Tb^4^+。通过半定量手段研究了SrMgF4中这一衡的平衡常数。

关键词: X射线衍射分析, 氟化钙, 氟化镁, 电子自旋共振, 铕, 铽, 氟化钡, 氟化锶, 电荷迁移

Emission of europium(Ⅱ) and europium(Ⅱ) have been observed in SrMgF4:xEu,yTb phosphors which are synthesized in Ar or Ar/H2 flow. The valence state of Eu is influenced by terbium. It is notable that the intensities of the ESR paeaks corresponding to Eu^2^+ are regularly changed when terbium ion is incorporated. The typical Tb3d XPS spectrum belonging to Tb^4^+ is also found when Eu is codoped. This phenomena can be explained by electron transfer mechanism Eu^3^++Tb^3^+→Eu^2^++Tb^4^+. And its equilibrium constant is studied by ESR technique.

Key words: X-RAY DIFFRACTION ANALYSIS, CALCIUM FLUORIDE, MAGNESIUM FLUORIDE, ELECTRON SPIN RESONANCE, EUROPIUM, TERBIUM, BARIUM FLUORIDE, STRONTIUM FLUORIDE, CHARGE-TRANSFER

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