Sr_(2-x)Ca_xSiO_4∶Eu^(2+),Dy^(3+)(0≤x<2)绿色长余辉发光材料的制备及发光性能  

Preparation and Optical Properties of Eu^(2+),Dy^(3+) Co-doped Sr_(2-x)Ca_xSiO_4 Green Long Persistent Phosphors via High-Temperature Solid State Reaction

作　　者：夏昌奎[1,2] 雷芳[1] 施鹰[1] 肖维勤 陆韬[1] 余爱民[2] 余剑峰[2] 

机构地区：[1]上海大学材料科学与工程学院,上海200444 [2]杭州诺贝尔集团有限公司,杭州311100

出　　处：《陶瓷》2017年第5期19-27,共9页Ceramics

摘　　要：以分析纯SrCO_3、CaCO_3、SiO_2、Eu_2O_3、Dy_2O_3为原料,采用低温预烧-还原气氛高温固相反应法制备了Eu^(2+)、Dy^(3+)共掺杂Sr_(2-x)Ca_xSiO_4∶Eu^(2+),Dy^(3+)(0≤x<2)陶瓷粉体,系统研究了Sr/Ca原子比、Eu、Dy掺量对所得粉体结晶特性、光致发光、热致发光、余辉性能的影响。结果表明,共掺杂粉体主晶相为斜方晶系α-Sr_2SiO_4,且随着Ca^(2+)浓度的增加,晶体结构发生畸变,衍射峰向高角度偏移。Dy^(3+)掺杂能够显著提高光致发光性能,最佳掺杂浓度为0.04mol%。从热释光与余辉分析表明,Ca^(2+)掺杂可引入新的陷阱能级,增强余辉发光,当Ca^(2+)掺杂浓度低于0.8%时,以Eu^(2+)取代Sr^(2+)的陷阱能级对余辉发光起主导作用;当Ca^(2+)掺杂浓度高于0.8%时,Eu^(2+)取代Ca^(2+)离子陷阱能级在余辉发光中起主导作用。Eu2＋ , Dya＋ co-doped Sr2-xCaxSiO4∶Eu2＋,Dy3＋（0≤x〈2） green long persistent phosphors were prepared by low temperature presintering and high temperature solid--state reaction routine in the H2 reduction atmosphere with stoi- chiometric and analytical reagent SrCO3 , CaCO3 , SiO2 , Eu2 03 and Dy2O3 as raw materials. X--ray diffractometer （XRD） was used to characterize the crystallinity of the as--prepared samples. The results show that the main crystalline phase of the sample is α- Sr2SiO4 , and the crystal structure is distorted with the increase of Ca2＋ concentration. The excitation spectra and emission spectra of the samples were measured by fluorescence spectrometer. The results reveal that the Dy3＋ can significantly improve the luminescent properties of the samples, and the optimum doping concentration is 0.04mol%. The relationship between the thermoluminescence and the afterglow were analyzed by the thermoluminescence spectra and the decay curves. It indicates that Ca2＋ doping can introduce new traps, and is conducive to the afterglow. When the doping concentration of Ca2＋ is lower than 0.8%, the trap level resulting from the substitution of Sr2＋ by Eu2＋ plays the leading role in afterglow process; When the doping concentration of Ca2＋ is higher than 0.8%, the trap level resulting from the substitution of Ca2＋ by Eu2＋ plays the leading role in afterglow process.

关 键 词：Sr2-xCaxSiO4∶Eu2+ Dy3+ 长余辉发光材料 高温固相反应法 光致发光 热释光 

分 类 号：TQ132.3[化学工程—无机化工]