蓝色长余辉发光材料Sr_2MgSi_2O_7:Eu^(2+),Ln^(3+)的合成和性质  

The Synthesis and Luminescent Properties of Blue-Emitting Long Afterglow Phosphors Sr_2MgSi_2O_7:Eu^(2+),Ln^(3+)

作　　者：翟永清[1] 孟媛[1] 曹丽莉[1] 周健[1] 

机构地区：[1]河北大学化学与环境科学学院,保定071002

出　　处：《材料导报》2007年第8期125-128,共4页Materials Reports

基　　金：河北省教育厅博士基金资助项目(B2004205);河北大学研究基金资助项目(y2004204)

摘　　要：采用凝胶-燃烧法合成了系列稀土掺杂的Sr2MgSi2O7:Eu20.+02,Ln30.+04(Ln=La,Ce,Nd,Sm,Gd,Tb,Dy,Ho,Er,Tm)蓝色长余辉发光材料,用X射线粉末衍射(XRD)、扫描电镜(SEM)、荧光分光光度计等对合成产物进行了分析和表征。结果表明:掺杂了不同稀土离子的Sr2MgSi2O7:Eu2+,Ln3+的晶体结构均为四方晶系结构;其激发、发射光谱的峰形、峰位基本无变化,激发光谱为一宽带,最大激发峰位于402nm处,次激发峰位于415nm处,与高温固相法制得的样品相比,激发峰发生了明显的红移;发射光谱也为一宽带,最大发射峰位于468nm附近,是由典型的Eu2+的4f5d-4f跃迁导致的,不同之处在于其激发光谱、发射光谱强度与余辉性质有所差别,其中Dy3+是最理想的共掺杂稀土离子,Sr2MgSi2O7:Eu2+,Dy3+的亮度最高、余辉时间最长,可达5h以上;而Sr2MgSi2O7:Eu2+,Sm3+的发光强度最低,余辉时间最短。A series of blue-emitting long afterglow phosphors Sr2MgSi2O7： Eu0.02^2＋, Ln0.04^3＋ （La, Ce, Nd, Sm, Gd,Tb,Dy, Ho, Er, Tm） are prepared by gel-combustion method. The as-synthesized phosphors are investigated by XRD, SEM and fluorescence spectrophotometer. The results indicate that Sr2MgSi2O7： Eu^2＋, Ln^3＋ phosphors have tetragonal crystal structure. The shape and position of peaks in excitation and emission spectrums keep almost no change with the variation of co-doped Ln^3＋. The excitation spectrum is a broad band, and the main peak is at 402nm and the secondary peak is at 415nm, showing an obvious red shift in comparison with that of sample by traditional solid reaction. The emission spectrum is also a broad band with the main peak at about 468nm, which is ascribed to Eu^2＋ ions typical transition from 4f5d to 4f. The co-doped Ln^3＋ has great effects on the intensity of excitation and emission spectrum, and the long afterglow properties. Among them, Dy^3＋ is the best one, and sample Sr2 MgSi2O7： Eu^2＋ ,Dy^3＋ has the highest brightness and longest duration time （over 5h）, while Sm^3＋ is the worst one, and sample Sr2 MgSi2 O7 ： Eu^2＋ , Sm^3＋ has the lowest brightness and shortest duration time.

关 键 词：Sr2MgSi2O7:Eu2+ Ln3+ 凝胶-燃烧法 激发光谱 发射光谱 长余辉 

分 类 号：TN104.3[电子电信—物理电子学]