白光LED用Sr(1-x)BaxSi2O2N2:Eu2+(0≤x≤1)荧光粉的制备和微结构改变相关的发光机理的探讨

项目名称： 白光LED用Sr(1-x)BaxSi2O2N2:Eu2+(0≤x≤1)荧光粉的制备和微结构改变相关的发光机理的探讨

项目编号： No.21301162

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 数理科学和化学

项目作者： 李国岗

作者单位： 中国地质大学（武汉）

项目金额： 24万元

中文摘要： 白光LED作为第四代照明技术具有高效、节能、环保、长寿命等优点，其中荧光粉对其性能有至关重要的作用。Eu2+激活的Sr(1-x)BaxSi2O2N2 (0≤x≤1)氮氧化物荧光粉，具有高的化学和热稳定性，且在近紫外和蓝光激发下其发光颜色可以从黄光到蓝光进行调节，引起越来越多的关注。然而至今其详细的发光机理还不清楚。因Eu2+的f-d跃迁发射受基质晶格环境（晶体场强度、配位环境、共价性等）影响较大，所以弄清楚Eu2+在Sr(1-x)BaxSi2O2N2:Eu2+中所处的微结构环境对于理解其发光机理是非常有帮助的。本课题拟定通过Rietveld结构精修和电子吸收光谱技术探测Eu2+周围的局部微结构环境，利用中子衍射技术来探测Eu2+周围的氮氧排列，探讨微结构改变对其发光性能的影响，提出微结构改变相关的发光机理，以期通过结构的微改变来调控荧光粉的发光颜色、提高发光效率和衍色性，改善热猝灭性能。

中文关键词： 氮氧化物硅酸盐；光致发光；稀土离子；阳离子取代；局部结构变化

英文摘要： White light-emitting-diodes (LEDs) are considered as the most promising 4th generation illuminating light sources due to their tremendous advantages including high efficiency, energy conservation, environmental protection, long lifetime and so on. Phosphors are indispensible component for white LED devices, which are responsible for the latter luminescence performance. Oxonitridosilicates phosphors are consists of the net of SiX4(X = O，N) tetrahedrons, which have highly chemical and thermal stability. Recently, the Eu2+-actived Sr(1-x)BaxSi2O2N2 (0≤x≤1) phosphors attract more and more attention due to their excellent color-tunable luminescence from yellow to blue under the excitation of near UV or blue light chips. However, their structure-related luminescence mechanisms are not clear. The emission of Eu2+ is attributed to f-d transition, which is easily affected by crystal environment of host lattice including crystal field strength, coordination environment, covalence and so on. Therefore, it is very improtant to ascertain the real microsturcture environment of Eu2+ in Sr(1-x)BaxSi2O2N2:Eu2+ (0≤x≤1)systems for us to understand the structure-related luminescence mechanism. Here, we will prepare pure-phased Sr(1-x)BaxSi2O2N2:Eu2+ (0≤x≤1) phosphors through the non-stoichiometric two-steps solid state process and

英文关键词： Oxonitridosilicate；Photoluminescence；Rare earth ions；Cation substitution；Local microstructure change