原位合成配合物Eu(DBM)3·2H2O在凝胶玻璃基质中的发光性能

在乙烯基改性的凝胶玻璃基质中原位合成了Eu(DBM ) 3·2H2 O配合物 ,用低温稳态光致发光 ( photoluminescence,PL)光谱和室温时间分辨光谱研究了其光谱性能。研究表明 :Eu3 离子在原位合成配合物Eu(DBM ) 3·2H2 O中的近邻对称性为C2V。在刚性的凝胶玻璃基质中由于分子间相互碰撞和剧烈振动而引起的热去激活和非辐射弛豫几率降低 ,更有利于有机配体到Eu3 离子5D0 能级的有效分子内传能 ,5D0 能级的寿命较在乙醇溶液中大得多     

Spectroscopic Properties and Local Structure of Eu3+ in Ge–Ga–S–CsBr (or CsCl) Glasses

Spectroscopic properties and local structure of Eu³⁺ in Ge–Ga–S–CsBr (or CsCl) glasses were investigated using fluorescence measurements and several spectroscopic methods. Fluorescence from Eu³⁺:⁵D₀→⁷F₂ was observed only from glasses with CsBr/Ga ratios greater than unity and disappeared at temperatures above 140 K. Phonon sideband (PSB) spectra revealed that Eu³⁺ ions are located next to halogen ions, which form part of well-structured complexes such as EuCl₃, tetrahedral [GaS_3/2Cl]⁻, subunits and/or Ga₂Cl₆. These new bonds showed reduced coupling strength compared with Eu³⁺–S bonds in Ge–Ga–S glass. Fluorescence line narrowing experiments showed little site-to-site variation of Eu³⁺ ions.     

溶胶-凝胶法制备SrAl_2O_4∶Eu~(2+),Dy~(3+)纳米发光材料

采用溶胶 -凝胶法在低温、还原气氛下制备了SrAl2 O4∶Eu2 ,Dy3 纳米长余辉光致发光材料。XRD分析表明 ,当焙烧温度为 80 0～130 0℃时 ,所合成的样品为SrAl2 O4单斜晶系晶体结构 ,晶格常数为 :a =0 .8442 4nm ,b=0 .882 2nm ,c =0 .5 160 7nm。 110 0℃以上观察到样品长余辉发光。激发光谱与发射光谱分析表明 :发射光谱是峰值位于 5 2 3nm的宽带谱 ,激发光谱是峰值在 2 40 ,330 ,378,42 5nm的连续宽带谱。样品在自然光照射后持续发出明亮的绿光。样品的合成温度从 110 0℃增加到 130 0℃ ,样品的颗粒尺寸不断增大。TEM和电子衍射分析表明 ,110 0℃烧结 4h的SrAl2 O4∶Eu2 ,Dy3 纳米粉末为结晶相 ,粒径为 30～ 40nm。     

Electroluminescence Based on Eu_(0.5)La_(0.5)(TTA)_3phen Doped Poly N-Vinylcarbazole

Organic electroluminescence (OEL) has been ex-tensively studied owing to its potential application inflat panel displays ever since the first double-layerOELdevice that has high efficiency and luminescencewas fabricated in 1987[1 ~4]. When compared withcommon smaller organic molecules and polymers ,rareearth (RE) complexes exhibit extremely sharp , well-defined spectral lines due to the emissions that origi-nate fromthe lanthanide metal ions .So the electrolu-minescence (EL) of REcomplexes…     

Site-selective spectroscopy of Eu-doped orthorhombic lanthanum and monoclinic yttrium polyphosphates

In order to study the influence in the change of the coordination environment of the cationic sites on the luminescent properties of rare-earth ions doping polyphosphates Ln(PO₃)₃ (Ln = La, Y) with two different structures, the time-resolved luminescence of the Eu³⁺ ion, used as structural probe, is reported. La(PO₃)₃ has an orthorhombic structure in which only one position with eight coordination is available for the cation, while Y(PO₃)₃ adopts the Yb(PO₃)₃ structure in which four slightly different octahedral sites are available for the trivalent rare-earth ion. Site-selective excitation of the ⁵D₀ level was performed and luminescence decay times of each Eu³⁺ site were measured at 77 K. The spectroscopic results are discussed and correlated with the structural data.     

Synthesis of Long Afterglow SrAl2O4 :Eu2+, Dy3+ Phosphor by Microemulsion Method

Long afterglow SrAl2 O4: Eu2 , Dy3 phosphor was synthesized by microemulsion method. The synthesized phosphor was characterized by XRD. XRD pattern indicates that the phosphor has monoclinic SrAl2 O4 crystal structre.The microstructure of the phosphor was investigated by SEM and TEM. The excitation spectrum, emission spectrum and afterglow decay curve were measured, the wide range of excitation wavelength indicated that the luminescent material could be excited by the light from ultraviolet ray to visible light, and the emission maximum was found to peak mainly at λem of 525 nm. The sample excited by ultraviolet visible light could emit bright green light.     

TTA-NA-Phen-Eu离子型配合物的合成及表征

以噻吩甲酰三氟丙酮(HTTA)、3-羟基2-萘甲酸(H2NA)和邻菲咯啉(Phen)为配体,合成了Na2[Eu(TTA)(NA)2(Phen)]新的离子型配合物,并用元素分析、红外光谱、紫外光谱对它进行了表征。     

以不同键合方式合成的Eu-AA-MMA共聚物的表征及荧光性质

用两种不同的键合方式，即先聚合再络合(先合成丙烯酸一甲基丙烯酸甲酯共聚物，再将铕离子(Eu^3 )引入此共聚物)和先络合再聚合(先合成丙烯酸铕，再合成丙烯酸铕一甲基丙烯酸甲酯共聚物)的方式将稀土元素Eu引入到高分子基体中。采用红外光谱、X射线衍射和DSC等手段对其结构、物相和热性能进行表征，确定铕与高分子基质发生配住。荧光光谱表明得到的配位聚合物是一种良好的光致发光材料，在紫外光下发出高亮度、单色性的特征红光。     

Eu^2＋激活的碱土铝酸盐长余辉发光材料的研究现状

简要介绍了Eu^2 作为碱土铝酸盐激活剂的荧光特性和影响材料发光特性的因素。综述了国内外在制备技术和机理方面的研究现状和该类材料的应用现状。最后指出了目前材料研究中存在的问题，并对今后的研究方向作了展望。     

Fluorescence determination of europium with pyridine-2,4,6-tricarboxylic acid

Europium can form a stable chelate with pyridine-2,4,6-tricarboxylic acid (PTA) with a ratio of 1:1 in aqueous. The system, having the maximum excitation and emission wavelengths at 311.0 nm and 616.3 nm, separately, shows a constant fluorescence intensity in the pH range of 11.0-12.0. The method has high selectivity and sensitivity as well as low effect from foreign ions. The optimum determinate conditions were obtained. The fluorescence intensity is a linear function of Eu^3 concentration in the range of 0.0029-1.5200 μg.mL^-1 and the limit of detection is 2.90 ng.mL^-1.