LaOBr:Tb,Gd中的能量传递

用激发谱、发射谱、荧光衰减、X射线衍射等方法研究了LaOBr:Tb_(0.0075)Gd_x(x<0.3)中的能量传递。探明在这种基质中Gd^(3+)对Tb^(3+)可发生有效的能是传递。λ_(ex)=275nm激发下未见Gd^(3+)的特征发射,只见b^(3+)的特征发射随Gd含量增加而增强,当x_(Gd)=0.30时,Tb^(3+)的发射积分强度为无Gd样品的～5.5倍。Gd^(3+)的存在使Tb^(3+)荧光衷减变慢,而Gd^(3+)—Tb^(3+)之间的能量传递是电偶极—电偶极相互作用的可能性较大。

稀土发光材料(La_(1-x)Gd_x)OBr:Tb,Ce中的能量传递

在紫外光激发下,(La_(1-x)Gd_x)OBr:Tb_(0.0075),Ce_y中Gd^(5+)、Ce^(3+)、Tb^(3+)可各自吸收激发能。Ce^(3+)和Tb^(3+)发光,Ge^(3+)不发光,但可将能量传递给Ce^(3+)和Tb^(3+)发光。Ce^(3+)和Tb^(3+)之间可能有可逆的能量传递。Gd的存在改变晶场分布,使Ce^(3+)激发带长波端红移,有利于Tb^(3+)+5D_3→Ce^(3+)→Tb^(3+5)D_4的能量传递,敏化人眼敏感的绿光发射,也有利于Tb^(3+)和Ce^(3+)发光的温度稳定性。

Energy Transfer in LaOBr:Tb,Gd

Energy transfer in LaOBr:Tb_(0.0075),Gd_x(x<0.30)was investigated via excitation spectra,emission spectra,fluorescence decay function and X-ray diffraction.Effective energy transfer from Gd to Tb was found. With excitation of λ=275nm,no Gd^(3+)but only Tb^(3+)emission has been observed,and the integrated intensity of Tb^(3+)emission increases with increasing Gd content up to～5.5 times(in the sample of x=0.30)compared to that of the sample without Gd.The existense of Gd in the sample slows down the Tb^(3+)flourescence decay,and most likely the electric dipole-dipole interaction dominates the energy transfer process.