摘要
研究了NaGd_(1-x)(Eu·Tb)_xTiO_4(X=0.01～0.5)化合物的合成,结构和光谱特性,观察了Li^+,Na^+,K^+和Mn^(4+),Ge^(4+),Si^(4+)对E_u^(3+)离子~5D-~7F跃迁荧光发射的影响,讨论了Gd^(3+)→Eu^(3+),Eu^(3+)-Tb^(3+)
In this paper, synthesis of a series of NaGd_(1-x)Dy_xTiO_4(x:0.01—1) and NaGd_(0.7)Ln_(0.5)·TiO_4(Ln:Ce, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm)at 1000℃ for 5 hours is studied. These compounds were found with a superstructure of the K_2NiF_4-type structure by X-ray powder diffraction. It is found from the emission and the excitation spectra of the compounds that the fluorescent intensities are stronger for the Eu^(3+), Dy^(2+) and Er^(2+) ions in the compounds.The Dy^(2+) emission Intensities, which is a function of Dy^(3+) concentration, decrease strongly and become very weak when x is more than 0.1 in NaGd_(1-x)Dy_xTiO4.The energy transfer phenomena in NaGd_(1-x)Dy_xTiO_4 have been observed and discussed. By using an approximate, it is possible to derive the critical distance for the energy transfer from Gd^(3+) to Dy_(3+). This approach implies a critical Dy^(3+) concentration, above which Dy^(3+) emission is quenched. This distance is approximately 6.46(?).Dy^(3+) is an effective activator for Gd^(3+) excitations, transfer being possible both from Gd^(3+) ~6I and ~6P levels. The spectral data indicate that there is probability of a high energy transfer from Gd^(3+) to Dy^(3+) ions, based on interaction between neighbor ions with fairly far apart to a large extent,
出处
《硅酸盐通报》
CAS
CSCD
北大核心
1989年第4期1-5,共5页
Bulletin of the Chinese Ceramic Society
基金
国家自然科学基金
