项目名称: 基于稀土离子掺杂的不同声子能量体系的近红外量子剪裁发光研究
项目编号: No.21301043
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: 林惠红
作者单位: 韩山师范学院
项目金额: 24万元
中文摘要: 本项目以研究量子效率大于1的新型近红外发光材料的量子剪裁发光机理为目标,采用高温固相和水热合成法,制备一系列以稀土离子Ce3+为敏化剂、Ho3+为激活剂、声子能量变化的氟化物-氟氧化物-氧化物体系为基质的发光材料。系统研究不同掺杂浓度的材料在紫外-可见、近红外波段的发光性能,包括基质声子能量、格位环境、基质结构对Ho3+近红外发光行为的影响。通过X射线粉末衍射(XRD)表征物相的组成和晶体结构,并用Rietveld方法对多格位占据样品的晶胞参数和原子占位数进行精修;结合荧光光谱、时间分辨光谱、荧光寿命等测试手段,并利用稀土离子的发光理论知识探索激活剂Ho3+在不同声子能量基质中的近红外双光子或三光子量子剪裁现象以及Ce3+到Ho3+之间的能量传递机理,构建Ho3+在不同声子能量基质中的量子效率计算模型,揭示Ho3+的近红外量子剪裁发光与基质结构的关系。
中文关键词: 近红外发光;量子剪裁;能量传递;长余辉发光;上下转换
英文摘要: In order to research the mechanism of near-infrared(NIR)quantum cutting in the luminescent materials with quantum yields greater than unity, a series of fluoride - fluoride oxide - oxide luminescent materials for mutative phonon energy on the basis of Ce3+ as a sensitizer,Ho3+ as an activator will be prepared. The luminescence properties will have been investigated under vacuum-ultraviolet (VUV), UV-vis, NIR excitations,including the influence of phonon energy in matrix,site symmetry and matrix structure on Ho3+ luminescent behavior. X-ray powder diffraction(XRD) and Rietveld refinement are used to characterize phase purity,crystal structrue, lattice parameters and occupation fractions. The NIR two or three photon quantum cutting luminescence of Ho3+ in different phonon energy matrix and the mechanism of the energy transfer from Ce3+ to Ho3+ will be explored by combination the test method of fluorescence spectroscopy, time-resolved spectra,fluorescence lifetime and the theoretical knowledge of rare earth ions.It will build the quantum efficiency computation model of Ho3+ in different phonon energy matrix, and reveal the relationship between the NIR quantum cutting luminescence of Ho3+ and the structure of matrix.
英文关键词: near-infrared(NIR) luminescence;quantum cutting;energy transfer;long-lasting phosphorescence;upconversion and down-shifting