荧光粉Sr_2SiO_4:Eu^(2+)中不同格位发光研究  

A study on the luminescence of different crystallographic sites for Sr_2SiO_4:Eu^(2+) phosphors

作　　者：吴霞[1] 李绪诚[1] 罗思远[1] 龚新勇[1] 邓朝勇[1] 

机构地区：[1]贵州大学理学院电子科学系,贵州省电子功能复合材料特色重点实验室,贵州贵阳550025

出　　处：《光电子．激光》2013年第11期2162-2168,共7页Journal of Optoelectronics·Laser

基　　金：贵州省科技计划(2011-2016;2012-3005;2011-2104;2010-4005;2009-15);贵阳市科技计划项目(2012101-2-4)资助项目

摘　　要：采用高温固相反应法制备了Sr2SiO4:xEu2+荧光粉,研究Eu2+所占据的Sr2SiO4中Sr1和Sr2两个不同格位及掺杂浓度和激发波长对格位发光的影响。荧光粉发射光谱为一双峰的宽发射光谱,可拟合为峰值位置位于480nm和530nm的两条高斯曲线,分别对应Eu2+所占据的Sr1和Sr2两个不同格位的发射。随着Eu2+掺杂浓度增加,Sr1和Sr2格位的发光强度均出现浓度猝灭现象,Sr2格位的长波长发射峰出现明显红移现象,而Sr1格位的短波长发射峰发生红移-蓝移-红移现象,这与Sr1和Sr2格位的优先占据以及格位间能量传递有关。随着激发波长的增加,Sr2格位的长波长发射的发光强度与Sr1格位的短波长发射的发光强度比值增加,占据不同格位的Eu2+对不同激发波长表现出明显的选择激发效应。Sr2SiO4：xEu2＋ samples were prepared using a so lid-state reaction method.Eu2＋ activators are located at two different cr ystallographic sites,namely high energy site and low energy site.The emission band of Sr2-xSiO4： xEu2＋ is a super-position of two distinct emission peaks at 480nm and 530nm.The luminesc ence properties of the two different crystallographic Sr2＋ sites are influ enced by Eu2＋ concentration and excitation wavelength.It is found that the concentration quenching phenomenon is observed at two sites,with the increase of doping concentration.With the decrease of the excitation light energy,the emission in tensity ratio of low energy site to high energy site is increasing.It shows tha t different sites have an obvious selective absorption.The process parameters ar e also investigated in this paper.

关 键 词：SR2SIO4 EU^2+ 格位 选择激发 浓度猝灭 能量传递 

分 类 号：O482[理学—固体物理]