SrAl_2O_4∶Eu,Dy长余辉材料缺陷化学分析  

Defect Chemistry of Long Afterglow Material SrAl_2O_4∶Eu, Dy

作　　者：胡劲[1] 孙加林[1] 刘建良[1] 施安[2] 徐茂[2] 高勤琴[2] 

机构地区：[1]昆明理工大学材料与冶金学院,云南昆明650031 [2]昆明贵金属研究所,云南昆明650221

出　　处：《中国稀土学报》2005年第S2期30-33,共4页Journal of the Chinese Society of Rare Earths

基　　金：云南省科研院所技术开发研究专项基金资助项目(2003KFZX-14)

摘　　要：利用活化Al-Sr合金粉末水解产物作为制备SrAl2O4长余辉材料的前驱体,并采用高温固相反应法制备出Sr1-xAl2O4∶Eu0.01,Dyx长余辉材料,并研究Dy掺杂量分别为x=0,0.01,0.02,0.03(%,原子分数)的长余辉材料荧光性能及长余辉特性。实验结果表明,随着Dy掺杂量的增大,长余辉材料初始发光亮度和余辉时间都随之增大。缺陷化学分析结果认为,所掺杂的稀土离子取代SrAl2O4晶格中的Sr2+离子格位,产生缺陷EuSr×,EuS.r和DyS.r,EuSr×为荧光发射中心,其浓度大小决定了长余辉初始发光亮度;EuS.r和DyS.r为带正电荷的缺陷,为满足体系电中性平衡,其周围吸引了带负电荷的缺陷,形成陷阱,可捕获带正电的空穴。其浓度大小,能级深浅将控制余辉时间。Hydrolysates of activated Al-Sr alloy powder was used as a precursor.The long afterglow material SrAl_2O_4∶Eu,Dy was prepared by high temperature solid reaction.Influence of concentration of Dy,x=0,0.01,0.02,0.03% on the phosphorescent properties and characters of afterglow was studied.The results show that the initial luminescent intensity and the duration time of SrAl_2O_4∶Eu,Dy increase as the concentration of Dy increases.The defect chemistry of long afterglow material SrAl_2O_4∶Eu,Dy was analyzed in detail.The doped rare erath ions occupy the lattice situation of Sr^(2+) in SrAl_2O_4 crystal structure.And then the impurity defect such as Eu~×_(Sr),Eu~·_(Sr) and Dy~·_(Sr) et al is formed.The initial luminescent intensity was decided by the concentration of Eu~×_(Sr) which is emission centers and charged positive.In order to keep neutral balance,the intrinsic defect V″_(Sr) charged negative was attracted around Eu~·_(Sr) and Dy~·_(Sr)-the impurity defect charged positive and formed the traps can trap the hole changed positive.The duration time was controlled by the concentration and energy level of V″_(Sr).

关 键 词：长余辉 铝酸锶 缺陷化学 陷阱 稀土 

分 类 号：O614.33[理学—无机化学]