摘要
于不同气流中,合成了MMgF_4:xEU,yTb复合氟化物燐光体.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Tb_3d(5/2)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SrMgF_4中这一平衡的平衡常数.
Emission of europium (II)and europium (III) 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 peaks corresponding to Eu2+ are regularly changed when terbium ion is incorporated. The typical Tb3d XPS spectrum belonging to Tb4+ is also found when Eu is codoped. This phenomena can be explained by electron transfer mechanism
Eu3+ + Tb3+→Eu2 + + Tb4+ .And its equilibrium constant is studied by ESR technique.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
1996年第5期468-474,共7页
Acta Chimica Sinica
基金
国家自然科学基金资助项目
