摘要
首次用高温固相反应合成了 Li_(0.5)MAl_(0.5)SiO_4:Eu,Bi(M=Mg,Ca,Sr,Ba)发光体,研究了基质中不同碱土金属离子对 Eu^(3+)和 Bi^(3+)的发光特性以及 Bi^(3+)敏化 Eu^(3+)发光性能和能量传递特点,得到了良好的基质组成和一些规律性结果。用395nm 紫外线激发,M=Mg 时的发光强度比 Y(V,P)O_4:Eu强约60%。Bi^(3+)发光的 Stokes 位移与 M(Ⅱ)的离子半径呈线性关系。
The luminophors of silicates Li_(0.5)MAl_(0.5)SiO_4:Eu,Bi(M=Mg,Ca,Sr,Ba)weresynthesized and luminescence properties of Bi^(3+)and Eu^(3+)ions were studied.The effects andregularities of M(Ⅱ)ions on the luminescence of Eu^(3+)and Bi^(3+)ions were also investigated.The study on the luminescence of silicates Li_(0.5)MAl_(0.5)SiO_4:Eu,Bi indicates that there areenergy transitions from Bi^(3+)to Eu^(3+)ion and that Bi^(3+)ions act as both sensitizer andco-activator.It is shown that the Stokes shift of Bi^(3+)luminescence becomes smaller linearlyas the radii of M(Ⅱ)ions decrease.The main emission is from ~5D_o-~7F_2 transition of Eu^(3+),whose intensity depends on the radii of M(Ⅱ)ions,i.e.the smaller the radius of M(Ⅱ),thehigher the Eu^(3+)(~5D_o-~7F_2)emission.Under UV excitation of 393nm,the luminescence intensity of Eu^(3+)inLi_(0.5)MgAl_(0.472)SiO_4:Eu_(0.025)Bi_(0.003)is 1.6 times that of Y(V,P)O_4:Eu,for both of^5D_o—~7F_2and of^5D_o—~7F_1transition emissions.The experiment results demonstrate that the optimum syn-thesis condition is 950℃ and 4 hours fired in twice for Li_(0.5)MgAl_(0.5)SiO_4:Eu,Bi and silicateLi_(0.5)MgAl_(0.5)SiO_4 is an excellent host lattice to obtain efficient photoluminescencematerials.
出处
《材料科学进展》
EI
CAS
CSCD
1990年第4期342-347,共6页
关键词
硅酸盐
光致发光
发光体
inorganic materials
photoluminescence
silicate
