架状硅酸盐结构中硫发光中心及其白光LED应用研究

Noticing a geographical advantage of extremely rich silicate mineral resources in Xinjiang, we research systemically luminescence properties and applications to white LED of natural silicates from Xinjiang by means of research methods of luminescence science, material science and mineralogy.　We reveal some important physical and chemical characters of silicates, such as components and structures, species and valence of trace elements, origins of luminescence, kinds of luminescent center, defects in crystal, energy-band structure and models of energy transfer, and reveal the luminescence mechanism. We also reveal the band structure and energy transfer of sulfur luminescence center in silicate frameworks through theory combined with experiment. For the investigation, we use the following analyzers; a powder X-ray diffraction (XRD) system, an electron probe microanalyzer (EPMA), an inductively coupled plasma-optical emission spectrometer (ICP-OES) and a steady state & fluorescence lifetime analyzer, a time-resolved fluorescence spectrometer, an absorption spectrometer. We prepare white LED used yellow phosphor with high luminance efficiency and environment protection, resulting from investigation on luminescence properties of silicates. Therefore, we offer theoretical basis and technical idea for developing and researching new luminescent materials. This research project conforms to the state's strategy of implementing the development of the western regions.By employing the advantage of rich nonmetallic mineral resources in Xinjiang, we can utilize the resources to development of industry in Xinjiang.

本项目基于白光LED的一些缺陷，结合新疆硅酸盐矿物资源极为丰富的地缘优势, 用发光学、材料学和矿物学的交叉研究方法，对新疆各地架状结构硅酸盐矿石的独特光致发光特性其应用探索进行系统研究，力求设计出一种新型高效的白光LED荧光粉。首先通过XRD、电子探针、ICP-OES、稳态/瞬态荧光光谱、吸收光谱等研究手段,进一步揭示新疆各地各类架状结构硅酸盐的结构和成分、微量元素种类和价态、发光起因、发光中心种类、能带结构、能量传递的方式等重要的物理和化学性质，并进一步揭示其光致发光机理。其次通过理论与实验相结合的办法，确定架状结构硅酸盐矿石内硫发光中心的能带结构和能量传递等。依据架状结构硅酸盐的结构成份及其发光性能研究，研制出色度好、高效率、环保的白光LED发光材料，为探索新基质的发光材料提供理论基础和技术路线。该研究项目，有利于发挥新疆非金属矿物资源优势，研究成果在发光材料领域具有很好的应用前景。

本项目基于白光LED的一些缺陷，结合新疆硅酸盐矿物资源极为丰富的地缘优势, 依据天然方钠石、方柱石等发光特性，运用发光学、材料学和矿物学的交叉研究方法，对新疆各地架状结构硅酸盐矿石的独特光致发光特性其应用探索进行系统研究，在实验室研究了单相白光发光材料NaAlSiO4:Ce3+, Sm3+的发光特性和能量传递机理、Na2CaSiO4:Sm3+，Eu3+系列荧光粉晶体结构的影响和材料发光特性、新型BaAl2Si2O8:Tb3+,Ce3+荧光材料可协调颜色性和架状硅酸盐Ca1-xAl2+xSi2O8中Eu3+和Eu2+ 的价态变化导致颜色可协调，一共有15种荧光材料的晶体结、掺杂微量元素的浓度对发光性能的影响、发光起因、发光中心种类、热稳定性、色品等重要的性质，并进一步揭示其发光机理。本课题组合成多种架状硅酸盐并通过掺杂不同稀土、金属离子制备出了多种蓝光、绿光、红光和白光发光材料。旨在制备亮度更高或颜色分布更合理或成本更低或环保的发光材料，为开发和研制新型LED荧光粉提供了理论依据和技术指导。