Ba^2＋离子对Sr2Al2SiO7∶Eu^2＋荧光体微结构及发光性能的影响  

The effects of Ba^(2+) ions on the microstructure and photoluminescence of Sr_2Al_2SiO_7∶Eu^(2+) phosphor

作　　者：蒙延双[1] 朱福良[1] 王达健[2] 

机构地区：[1]兰州理工大学材料科学与工程学院,甘肃兰州730050 [2]天津理工大学材料物理研究所,天津300191

出　　处：《功能材料》2008年第7期1078-1080,共3页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(50364002)

摘　　要：采用复合胶体喷雾工艺制备了Ba2+离子掺杂的Sr2-xBaxAl2SiO7∶Eu2+(x=0、0.1、0.2、0.4)荧光体。研究了Ba2+离子在基质Sr2Al2SiO7中的取代位置和机理,分析了Ba2+离子取代Sr2+离子对基质微结构及Sr2Al2SiO7∶Eu2+荧光体发光性能的影响。XRD结果表明Ba2+离子取代Sr2+格位进入Sr2Al2SiO7晶格,导致晶胞体积增大。进入Sr2Al2SiO7晶格的Ba2+离子由于电负性较大,处在其周围的Eu2+离子外层电子受Ba2+离子影响,电子云膨胀,使发光波长发生红移。同时,掺入Ba2+离子后Sr2-xBaxAl2SiO7晶场强度增强,晶体场对Eu2+离子5d能级的劈裂程度增大,劈裂重心下降。Ba2+离子掺杂的Sr2-xBaxAl2SiO7∶Eu2+(x=0、0.1、0.2、0.4)荧光体发射主峰位于520nm,与未掺杂Sr2Al2SiO7∶Eu0.022+荧光体的发射峰相比出现红移。Srz-xBaxAl2 SiO7： Eu^2＋ （x=0, 0.1, 0.2, 0.4） phosphors was prepared by spraying of composite sol technique. The substitution mechanism of Ba^2＋ ions for Sr2＋ in Sr2 A12 SiO2 lattice was discussed. The effects of the substitution on the microstructure and on the photoluminescence characteristic of Sr2Al2SiO7： Eu^2＋ phos- phor were researched. XRD results show that the Ba^2＋ ions substitute for Sr^2＋ sites on SrzAlzSiO7 lattice. It is indicated that the Ba^2＋ ions substitution result in the electron cloud expand of Eu^2＋ ion and consequently cause a red shift of the emission spectra of Sr2Al2SiO2：Eu^2＋ phosphor. On the other hand, the substitution of Ba^2＋ for Sr^2＋ results in increasing of the crystal field intensity of Srz Alz SiOz. The split of 5d energy level of Eu^2＋ increases and the emission spectra of Sr2Al2SiO7：Eu^2＋ phosphor red shifts to 520nm when partially substitute Sr^2＋ with Ba^2＋ ions.

关 键 词：荧光体 Sr2Al2SiO7∶Eu2+ Ba2+离子 微结构与光谱 

分 类 号：TB39[一般工业技术—材料科学与工程]