Photoluminescence properties of Y_(0.75-x)Gd_xAl_(0.10)BO_3:Eu_(0.10)~(3+),0.05R~(3+)(R= Sc,Bi) (0.00 ≤ x ≤ 0.45)

Y 0.75 -x Gd x Al 0.10 BO 3 :Eu0.10 3+, 0.05R 3+ (R=Sc, Bi) (0.00 ≤ x ≤ 0.45) powder samples are prepared by solid-state reaction and their luminescence properties are investigated. With the replacement of Y 3+ ions by Sc 3+ (or Bi 3+ ) and Gd 3+ ions in (Y,Al)BO 3 :Eu, the intensities of emission at 254 and 147 nm are remarkably improved, because Sc 3+ ions can absorb UV light and transfer the energy to Eu 3+ ions efficiently. Moreover, Gd 3+ and Bi 3+ ions act as an intermediate "bridge" between the sensitizer and the activator (Eu 3+ ) in energy transfer to produce light in the (Y, Gd)BO 3 :Bi 3+ , Eu 3+ system more effectively. After doping an appropriate concentration of Gd 3+ into Y 0.50 Gd 0.25 Al 0.10 BO 3 :Eu0.01 3+ , Bi0.05 3+ , the emission intensity reaches its maximum, which is nearly 110% compared with the red commercial phosphor (Y,Gd)BO 3 :Eu and better chromaticity coordinates (0.650, 0.350) are obtained.     

PDP用发光材料的研究进展

目前,商用PDP三基色荧光粉主要为红色(Y,Gd)BO₃:Eu³⁺,绿色Zn₂SiO₄:Mn²⁺、BaAl₁₂O₁₉:Mn²⁺或(Gd, Y)BO₃:Tb³⁺,蓝色BaMgAl₁₀O₁₇:Eu²⁺。然而,以上3种荧光粉均存在发光效率低的问题;另外,(Y, Gd)BO₃:Eu³⁺的色纯度较差,Zn₂SiO₄:Mn²⁺和BaAl₁₂O₁₉:Mn²⁺的衰减时间较长,(Gd,Y)BO₃:Tb³⁺亮度不足,BaMgAl₁₀O₁₇:Eu²⁺的稳定性较差,这些因素在一定程度上制约了其发光和显示性能。本文总结了目前红、绿、蓝三种发光材料的真空紫外发光机理以及发光性能改进的研究进展,同时,对目前开发新型PDP用发光材料的研究也进行了介绍。     

Photoluminescence properties of Y0.75-xGdxAl0.10BO3:Eu3+0.10, 0.05R3+ (R= Sc, Bi) (0.00≤x≤0.45)

Y$_{0.75 - x}$Gd_xAl_0.10BO$₃:Eu$^{3+}_0.10, 0.05R³⁺ ($R$=Sc, Bi) ($0.00 ≤ x ≤ 0.45$) powder samples are prepared by solid-state reaction and their luminescence properties are investigated. With the replacement of Y³⁺$ ions by Sc³⁺$ (or Bi³⁺)$ and Gd³⁺$ ions in (Y,Al)BO$₃:Eu, the intensities of emission at 254 and 147~nm are remarkably improved, because Sc³⁺$ ions can absorb UV light and transfer the energy to Eu³⁺$ ions efficiently. Moreover, Gd³⁺$ and Bi$^{3 + }$ ions act as an intermediate ``bridge' between the sensitizer and the activator (Eu³⁺)$ in energy transfer to produce light in the (Y, Gd)BO$₃:Bi³⁺$, Eu³⁺$ system more effectively. After doping an appropriate concentration of Gd³⁺$ into Y$_{0.50}$Gd$_{0.25}$Al_0.10BO$₃:Eu³⁺_{0.01}$, Bi$^{3+}_{0.05}$, the emission intensity reaches its maximum, which is nearly 110{\%} compared with the red commercial phosphor (Y,Gd)BO$₃:Eu and better chromaticity coordinates (0.650, 0.350) are obtained.     

配体辅助机械化学法制备CsPbBr3-Cs4PbBr6复合NCs及其发光强度和稳定性研究

在室温下使用机械化学法,通过引入微量甲醇与油胺作为配体辅助合成,成功制备了CsPbBr₃-Cs₄PbBr₆ 钙钛矿复合纳米晶(NCs)。对该纳米晶进行粉末X射线衍射(XRD)、元素含量分析(EDS)、紫外可见吸收光谱(UV-Vis)、光致发光(PL)光谱及透射电子显微镜(TEM)等测试。与未添加甲醇的样品相比,添加0.85 mL甲醇的样品发光强度提高了58%,量子产率(PLQY)从11%提高到55%,并且复合NCs中Cs₄PbBr₆的存在使得样品的室温稳定性得到改善。本实验证实了机械化学法制备过程中甲醇的引入可以调整复合物纳米晶的成分,从而显著提高产物的发光强度和稳定性,为室温合成发光纳米晶提供了新思路。     

Sr2MgSi2O7∶Eu2+,Eu3+发光性能及颜色调控

采用静电纺丝法在不同气氛下制备了Sr₂MgSi₂O₇∶Eu²⁺,Eu³⁺纤维,研究其晶体结构和形貌;将纤维与聚二甲基硅氧烷(PDMS)复合后获得Sr₂MgSi₂O₇∶Eu²⁺,Eu³⁺-PDMS复合材料,研究其光致发光和应力发光性能。研究结果显示,氮气、空气下制备样品的XPS图谱同时出现Eu²⁺和Eu³⁺结合能特征峰;在360 nm和395 nm激发下复合材料的光致发光光谱中,不但有Eu²⁺位于469 nm处的蓝色宽带发射,还包含Eu³⁺位于615 nm的多个红色窄带发射。因为Eu³⁺在电荷补偿下还原成Eu²⁺并在刚性结构保护下不被氧化,证实了Eu³⁺在Sr₂MgSi₂O