Bioinspired Design of SrAl2O4:Eu2+ Phosphor

A phosphor based on Sr_0.97Al₂O₄:Eu_0.03 with a biomorphous morphology is manufactured via vacuum assisted infiltration of wood tissue (Pinus sylvestris) with a precursor nitrate solution. The nitrate solution penetrates homogeneously into the uniform arrangement of rectangular shaped tracheidal cells of the wood tissue. According to scanning electron microscopy, the original wood cell walls are completely transformed retaining the original wood structure. The major crystalline phase is monoclinic SrAl₂O₄, detected by X‐ray diffraction and confirmed by Rietveld refinement. Energy‐dispersive X‐ray analysis proves the homogeneous conversion of the original wood cell wall into Sr_0.97Al₂O₄:Eu_0.03 struts. The optical properties of the resulting phosphor material are determined by photoluminescence and cathode‐luminescence spectroscopy in scanning electron microscopy. The biotemplated Sr_0.97Al₂O₄:Eu_0.03 shows a characteristic green emission at 530 nm (2.34 eV). Shaping biomorphous SrAl₂O₄:Eu²⁺ phosphor with a microstructure pseudomorphous to the bioorganic template anatomy offers a novel approach for designing micropatterned phosphor materials.     

SrAl2O4 ：Eu2+和SrAl2O4 ：Eu2+，Dy3+长余辉和热释光谱

对比研究了SrAl2O4:Eu2+和SrAl2O4:Eu2+,Dy3+的余辉特性和热释光谱,并探讨了Dy3+的掺杂对SrAl2O4:Eu2+陷阱能级的影响。XRD晶相分析表明: Eu2+和Dy3+的掺杂并没有改变SrAl2O4的晶体结构。发光分析表明：Dy3+的掺杂没有改变SrAl2O4:Eu2+的光致发光光谱和发光中心。热释光谱对比分析结果显示：Eu2+的掺杂在SrAl2O4的禁带中引入了两个深度不同的陷阱能级;Dy3+的掺杂并不改变原来陷阱能级的深度,却能够显著地增加原来浅陷阱能级的密度,从而改善了SrAl2O4:Eu2+的余辉特性。不同等待时间的热释光谱曲线显示：在室温下,不同陷阱能级衰减规律的差异以及陷阱能级间存在的电子转移,可能造成了SrAl2O4:Eu2+,Dy3+长余辉材料复杂的余辉衰减规律。     

纳米蓝粉CaAl2O4:Eu2+的制备与研究

将超声波运用于沉淀法合成了彩色PDP用纳米级蓝粉CaAl2O4：Eu^2 用X射线粉晶衍射(XRD)、透射电镜(TEM)、荧光分光光度仪及PDP真空紫外荧光光谱测试系统对样品的性能进行了表征。XRD显示在1350℃煅烧就能得到单相的CaAl2O4基质，相对于高温固相反应法烧结温度降低了150℃；分别用高温固相法、传统的沉淀法和运用了超声波的沉淀法制备出了CaAl2O4：Eu^2 产物，结果表明运用了超声波的沉淀法制备出的纳米CaAl2O4：Eu^2 未发生团聚，粒度达70nm，相对发光强度大大提高；同时研究了Eu^2 对CaAl2O4：Eu^2 的发光性能的影响，确定了Eu^2 的最佳掺杂浓度；并研究了在真空紫外条件147nm激发下纳米CaAl2O4：Eu^2 的发光性能，结果表明其余辉时间为2．51ms，相对发光强度为商用PDP蓝粉BaMgAl10O17：Eu^2 的92％，色坐标y值为0．0426，比：BaMgAl10O17：Eu^2 的色坐标，值小，说明纳米CaAl2O4：Eu^2 的色彩重现域更广，在PDP应用中会具有较好的前景。