X射线影像存储材料BaF_xCl_（2－x）Eu~（2＋）的制备及其热释发光和

本文采用了不同温度下两次烧结的新方法，制备了系列Ｘ射线影象存储材料ＢａＦ＿ｘＣｌ＿（２－ｘ）：Ｅｕ￣（２＋）（ｘ＝０．９０，０．９５，１．００，１．０５，１．１０１．１５）。通过改变Ｆ／Ｃｌ比值，研究了在Ｘ射线辐照后ＢａＦ＿ｘＣｌ＿（２－ｘ）：Ｅｕ￣（２＋）的热释发光性质，给出了热释发光峰的温度与缺陷种类的关系。最后，我们研究了ＢａＦ＿ｘＣｌ＿（２－ｘ）：Ｅｕ￣（２＋）的光激励发光性质，给出了Ｆ／Ｃｌ比值与光激励发光强度的关系。     

BaFCl：Eu^2＋,Eu^3＋的光激励发光过程

本文首次报道了ＢａＦＣｌ：Ｅｕ＾２＋,Ｅｕ＾３＋的光激励发光。实验结果发现,在ＢａＦＣｌ：Ｅｕ中Ｅｕ＾３＋对Ｅｕ＾２＋的光激励发光有增强作用。在ＢａＦＣｌ：Ｅｕ的光致发射光谱中同时观察到对Ｅｕ＾２＋、Ｅｕ＾３＋及基质的本征发射,而光激励发射光谱中只观察到Ｅｕ＾２＋的发射,表明光致发光与光激励发光存在着很大的差异。这些结果表明,发光中心Ｅｕ＾２＋、Ｅｕ＾３＋及基质之间存在着相互作用和能量传递。本文提     

X射线影像存储与再现用发光材料MFX：Eu^2＋的研究现状及应用前景

二价稀土离子（Ｅｕ￣（２＋）、Ｓｍ￣（２＋））激活的碱土金属氟卤化物ＭＦＸ（Ｍ＝Ｃａ、Ｓｒ、Ｂａ；ｘ＝Ｃｌ、Ｂｒ、Ｉ）具有多种性能。本文介绍了这类材料的结构和性能。回顾了其光激励发光的研究现状。并探讨了其作为Ｘ射线影像存储与再现用发光材料的应用前景及存在问题。     

氟化物中Eu^2＋,Ce^3＋的浓度猝灭及其机理

本文详细地研究了ＢａＹＦ５和ＫＣａＦ３基质中Ｅｕ＾２＋、Ｃｅ＾３＋浓度对其发光的影响，发现两基质中Ｅｕ＾２＋、Ｃｅ＾３＋的猝灭浓度都较低；提出了Ｅｕ＾２＋、Ｃｅ＾３＋的浓度猝灭机理，计算了猝灭浓度和临界距离，并与实验结果进行了比较。     

表面扩散法制备BaMgAl10O17:Eu2+荧光体

本文提出“表面扩散法”的思想并应用于稀土三基色发光材料中蓝色组份ＢａＭｇＡｌ１０Ｏ１７：Ｅｕ＾２＋的制备。结果表明,同直接高温固相法制得的荧光体相比,利用表面扩散法制备的蓝色荧光体ＢａＭｇＡｌ１０Ｏ１７：Ｅｕ＾２＋,在相同的发光亮度条件下,激活剂Ｅｕ＾２＋的浓度可以大为降低,从而为降低这类材料的成本提出了依据和可能。     

稀土正硼酸盐Ln_(1-x)BO_3:Eu_x(Ln=Y,Gd)的结构与发光特性

用溶胶－凝胶法和高温固相反应分别制备了纳米量级和常规尺度的稀土正硼酸盐荧光粉ＬｎＢＯ３：Ｅｕ（Ｌｎ＝Ｙ,Ｇｄ）,测量了它们的激发光谱并首次观察到了ＹＢＯ３：Ｅｕ中Ｅｕ３＋的７Ｆ０→５Ｄ０跃迁的 Ｎｅｐｈｅｌａｕｘｅｔｉｃ效应．根据低温下的激发光谱,发射光谱以及变温条件对发光光谱的影响,ＹＢＯ３中Ｌｎ３＋所占据的两种格位的对称性被修正为Ｃ３和Ｄ３在不同方法制备的样品中观察到了不同的发光强度和猝灭浓度,缺陷的影响是产生这种不同的原因,退火样品的发光和拉曼散射谱的变化反映出掺杂的杂质Ｅｕ３＋的团聚化是可能的缺陷来源．     

高温高压合成的硅酸锶铕铋的发光特性

用高温高压方法合成了Ｓｒ２ＳｉＯ４：Ｅ３＋ｕ，Ｂｉ３＋和ＳｒＳｉＯ３：Ｅｕ３＋，Ｂｉ３＋研究了合成压力对其发光性能的影响，与用溶胶－凝胶共沉淀法和常压高温法合成的产品作比较．常压制备的ＳｒＳｉＯ３：Ｅｕ３＋，Ｂｉ３＋为六角结构，而在２．３４—４．１０ＧＰＳ的合成压力范围内，它转变为反正交结构；常压下Ｓｒ２ＳｉＯ４：Ｅｕ３＋，Ｂｉ３＋为单斜结构，在４．２ＧＰａ的合成压力下，未发现其结构相变．高压合成产物的发光强度和相对量子发光效率降低，半宽度明显增加，且伴有红移发生．发光强度的改变是压致晶场的变化引起的     

蓝色发光材料MGa2S4:Ce(M=Ca,Sr)发光特性的研究

制备了可用于蓝色ＴＦＥＬ的粉末发光材料ＭＧａ２Ｓ４：Ｇｅ（Ｍ＝Ｃａ，Ｓｒ）地其昌体结构进行了Ｘ射线分析，测量并其激光光谱和发射光谱，研究了Ｃｅ＾３＋浓度的变化对ＣａＧａ２Ｓ４：Ｃｅ和ＳｒＧａ２Ｓ４：Ｃｅ的激光光谱，发射光谱、色纯工及发光强度的影响，同时研究了基质组分的改变对发光特性的影响，结果表明，ＣａＧａ２Ｓ４：Ｃｅ和ＳｒＧａ２Ｓ４：Ｃｅ的可发射纯蓝色光，色纯度好，对ＣａＧａ２Ｓ４：Ｃｅ来说，实     

Eu2+在多铝酸钠体系中的发光

应用高温固相法合成了Ｎａ的多铝酸盐,并研究了Ｅｕ＾２＋在体系中的发光性能,结果表明,Ｎａ１＋ｘＭｇＡｌ１１－ｘＯ１７体系在整个组成范围内保持Ｎａ的β－Ａｌ２Ｏ３结构不变,而对于Ｎａ１．６７－２ｘＢａｘＡｌ１０．３３Ｏ１７体系,在ｘ＝０．３０附近体系结构发生转变,ｘ〈０．３０,体系形成Ｎ的β－Ａｌ２Ｏ３结构的固溶体,ｘ〉０．３０,体系形成Ｂａ的β－Ａｌ２Ｏ３结构的有序体;与体系组成的和结构的变化相对     

BaClF：Eu^2＋的微波辐射合成

报道了用微波辐射法合ＢａＣｌＦ：Ｅｕ＾２＋荧光体，Ｘ－射线粉末衍射测定其相结构为四方晶系，晶胞参数为ａ＝０．４３８９３ｎｍ，ｃ＝０．７２２３ｎｍ测定了最大激发峰和最大发射峰；在２５４ｎｍ光激发下，测定了色坐标。     

Process of Photoluminescence and Photostimulated Luminescence in BaFBr:Eu Phosphors

The photoluminescence (PL) and photostimulated luminescence (PSL) of BaFBr:Eu phosphors are reported. In the photoluminescence of BaFBr:Eu, the emission of Eu2+ , e-h recombination and Eu3+ have been observed, while in the photostimulated luminescence only the emission of Eu2+ was observed. This phenomenon may be explained well by the suggestion of a two-band model for the host emission in which the host emission energy may transfer to Eu2+. The difference of excitation in those two processes results in different transfer rates which makes the PL and PSL emission different.     

Luminescence of Eu2+ in Barium Octoborate

The luminescence of Eu2+ in low- and high-temperature modified BaB8O13 are reported. The valance change from Eu3+ to Eu2+ is observed when the samples are prepared in air. Eu2+ shows f-d transition at room temperature under UV excitation. The temperature dependency of the emission of Eu2+ in the hosts is studied. Multiple crystallographic sites for Eu2+ in the lattice are observed.     

Y2O3:Eu3+纳米晶的制备及其光学性能研究

以NaOH,Y(NO3)3.6H2O和Eu(NO3)3.6H2O为前驱体,通过添加络合剂PEG-2000,采用水热法,成功地合成了Y2O3∶Eu3+纳米棒和纳米管,并采用先进的测试手段对其结构和性能进行了表征与测试。探讨了Y2O3∶Eu3+纳米棒和纳米管的生长机制,同时研究了Y2O3:Eu3+纳米晶的光致发光性能。研究结果表明,水热温度、反应时间、NaOH的添加量和PEG-2000对产物形貌有着非常重要的影响,所制备的材料具有Eu3+的特征红光发射,并在Eu3+的掺杂量为5%(摩尔分数)时样品发光最好。     

热释发光-正电子湮灭法研究SrAl2O4基磷光体长余辉发光机制

利用传统陶瓷制备方法合成了长余辉SrAl2O4：Eu，Dy发光粉材料，并利用热释发光—正电子湮灭法对该材料的发光性能及机理进行了研究。研究结果表明，掺杂的Eu在基质材料中主要充当发光中心，而Dy离子主要充当陷阱能级。正电子湮灭试验结果表明，Sr0.94Al2O4：Eu0.02和Sr0.94Al2O4：Eu0.02，Dy0.04存在带负电中心的缺陷，共掺杂的Dy^3 进到Sr^2 位，同时产生一定量的Sr空位，热释发光谱结果表明，单掺杂Eu离子的磷光体中缺陷陷阱深度较深，约为0．95eV，随着Dy的共掺杂，热释发光强度相应增加，陷阱深度降为0．51eV，对于长余辉发光机制，认为陷阱能级捕获的空穴与介稳态(Eu^1 )^*的复合，导致了长余辉现象的发生，并且由于陷阱深度的变化，导致余辉性能出现较大的差异。     

One-step synthesis and optical properties of water-soluble and amine-functionalized Dy3+-doped BaFCl nanocrystals

Water-soluble and amino-functionalized luminescent Dy3+-doped BaFCl nanocrystals have been synthesized for the first time via a facile one-step modified solvothermal method with polyethyleneimine (PEI) as capping agent. The obtained BaFCl:Dy3+ nanocrystals have a size of about 40 nm, remain stable in aqueous solutions under different pH, and exhibit intense visible luminescence of Dy3+. The synthesized nanocrystals featuring long-lived luminescence may have potential applications as time-resolved photoluminescent probes for bio-applications.     

烧成条件对长余辉蓄光玻璃光学性能的影响

以ＳｒＡｌ_２Ｏ_４：Ｅｕ,Ｄｙ长余辉发光粉体和低熔点硼硅酸盐玻璃为原料,在一定条件下合成了长余辉蓄光玻璃．研究结果表明,烧成温度和保温时间对该玻璃的发光效果影响较大．温度越高,保温时间越长,由于空气的氧化作用,蓄光玻璃的发光效果越差,本试验控制烧成温度在７５０～８００℃间,保温时间在 １０ｍｉｎ以内,能合成性能较好的蓄光玻璃．余辉衰减曲线表明蓄光玻璃的发光性能较之原始发光粉体有所下降．ＳＥＭ分析表明,低温合成的蓄光玻璃中,所含能继续保持发光性质的粉体料,明显比高温合成样要多．     

Eu掺杂KNN陶瓷的制备及可调性发光研究

稀土离子掺杂铁电陶瓷是一类新型光致变色材料, 在光开关、光信息存储等领域具有潜在应用价值。本研究采用水热法制备了(K_0.5 Na_0.5)_1-xEu_xNbO₃(KNN:xEu)前驱体粉体, 随后利用高温烧结得到对应陶瓷样品。在465 nm激发下, 观察到615 nm处有强的红色发光, 对应于Eu ³⁺的 ⁵D₀→ ⁷F₂跃迁。通过紫外光照射, KNN:Eu陶瓷从乳白色变为深灰色。随后经过200 ℃加热10 min, 着色陶瓷又变回到初始颜色, 显示出良好的光致变色行为。紫外照射和反复加热循环可以有效调控该陶瓷的发光强度。且经过多次循环之后, 发光强度没有明显衰减。在紫外光照射下, KNN:0.06Eu陶瓷发光强度的可调比(ΔR_t)高达83.9%, 说明发光具有良好的可调性。进而结合发光中心和色心之间的能量转移, 对KNN:Eu陶瓷的光致变色和发光机理进行了解释。     

一种高分子相变发光材料的制备和性能

利用聚对苯二甲酰氯对聚乙二醇端基进行改性,制备出了聚乙二醇端基活化产物PEG-PTC,然后将其作为配体,通过化学键连接上功能性的发光基团(发光基团的构成主要以稀土铕为中心),合成了带有新型配体PEG-PTC的和1,10-邻菲口罗啉的稀土铕-聚乙二醇型配合物。通过配体、配合物的红外光谱、DSC、TG等的测试,对其组成、结构和性能进行分析。结果表明,含有新型配体PEG-PTC的稀土铕-聚乙二醇型的配合物不仅具有相变功能,同时具有优异的荧光特性,新型配体与稀土离子的激发态能级间具有较好的能级匹配,并且具有良好的热稳定性。     

Luminescence study on Eu(3+) doped Y(2)O(3) nanoparticles: particle size, concentration and core-shell formation effects

Nanoparticles of Eu(3+) doped Y(2)O(3) (core) and Eu(3+) doped Y(2)O(3) covered with Y(2)O(3) shell (core-shell) are prepared by urea hydrolysis for 3?h in ethylene glycol medium at a relatively low temperature of 140?°C, followed by heating at 500 and 900?°C. Particle sizes determined from x-ray diffraction and transmission electron microscopic studies are 11 and 18?nm for 500 and 900?°C heated samples respectively. Based on the luminescence studies of 500 and 900?°C heated samples, it is confirmed that there is no particle size effect on the peak positions of Eu(3+) emission, and optimum luminescence intensity is observed from the nanoparticles with a Eu(3+) concentration of 4-5?at.%. A luminescence study establishes that the Eu(3+) environment in amorphous Y (OH)(3) is different from that in crystalline Y(2)O(3). For a fixed concentration of Eu(3+) doping, there is a reduction in Eu(3+) emission intensity for core-shell nanoparticles compared to that of core nanoparticles, and this has been attributed to the concentration dilution effect. Energy transfer from the host to Eu(3+) increases with increase of crystallinity.     

Luminescence properties of CsI:Eu crystals

The work is aimed to research of CsI:Eu single crystals’ luminescence at different excitations in the wide temperature range (from 8 to 300 K) and admixture concentration from 10⁻⁴% up to 10⁻¹% of Eu²⁺ ions. This study was directed to separation of different luminescence mechanisms and luminescence quenching explore. It is found that due to the temperature quenching the room temperature yield is decreased in order of magnitude even for heavy Eu doped CsI crystals. Intense low temperature luminescence band at 441–448 nm connected with Eu²⁺ 4f⁶ 5d → 4f⁷ radiative transition is observed. The results obtained show that the excitonic mechanism plays the main role in energy transfer process to Eu²⁺ ions and this is the reason for relatively low light yield of this emission at RT. The nature of the additional emission bands (410, 450, 480 and 500 nm) are apparently caused by the significant non-isomorphism of cations and/or by the presence of oxygen-containing admixtures.