纳米Eu0.10Y1.90-xNdxO3-δ的光致发光特性及浓度猝灭研究

使用超声波作用下的均匀沉淀法,制备了Eu0.10Y1.90-xNdxO3-δ纳米晶荧光粉,用X射线粉末衍射、荧光光谱等对其进行表征.研究了掺杂Nd3 离子对Y2O3∶Eu3 晶格常数、晶粒尺寸及室温光致发光特性的影响.由不同掺杂浓度x=0~0.18下样品的发射光谱强度变化曲线得到猝灭浓度值,探讨了掺杂Nd3 的样品荧光浓度猝灭的机理.发光强度与浓度的关系表明,掺杂离子之间存在的Eu3 -Nd3 或Nd3 -Nd3 间交换相互作用,是导致掺杂样品浓度猝灭的主要原因.     

不同碳酸铵试剂对共沉淀法制备的GDC粉性状的影响

近年来工作温度在500￣700℃的中温固体氧化物燃料电池(IT-SOFC)受到广泛关注。稀土掺杂氧化铈尤其是钐、钆掺杂氧化铈在中温下的离子电导率远高于钇掺杂氧化锆(YSZ),是较为理想的IT-SOFC电解质材料。由于掺杂氧化铈难于烧结,不便于制备致密的电解质膜,通过提高掺杂氧化铈粉体细度来降低其烧结温度,是近年来该材料应用领域的一个研究热点。已有各种合成掺杂氧化铈纳米粉的报道,如采用共沉淀法、固态反应法、水热处理法、燃烧法、溶胶-凝胶法等等。其中碳酸盐共沉淀法由于具有成本低、设备简单以及合成粉体细度高等优点而倍受青睐。通…     

铽与邻氨基苯基苯甲酸配合物的合成、表征及荧光性质

选择不同的pH值,在乙醇-水溶液中合成了铽与邻氨基苯基苯甲酸固体配合物.通过元素分析、摩尔电导、热分析、红外光谱、紫外光谱,表征并确定了配合物的化学组成为TbL4K·nH2O(n=1,2).同时,在不同pH值下合成得到的配合物的荧光性质也得到了测试和讨论,表明pH=10.0时配合物TbL4K·2H2O在544 nm处5D4→7F5跃迁的发射峰为最强.     

碘掺杂的3-乙基-5-[2-(3-乙基-2苯并噻唑啉基)亚乙基]罗丹宁的结构与电性能

The merocyanine dye 3-ethyl-5-(2-(3-ethyl-2-benzothiazolinylidene)-ethylidene)-rhodanine (BTER) known as Agfa-10 has been found to have a good photoconductivity as solution cast film. In this paper iodine-doped BTER was obtained by doping with iodine vapor. Its structure was investigated with the following characteristies. 1 The doped iodine had been excited as I_3~- anion. 2 Because the electron located on the sulphur atom was transferred to iodine, the charge transfer complex of (BTER-I_3) formed. 3 During the iodine doping process, BTER changed from α-form to β-modification. These had been identified by X-ray diffraction, VIS-absorption spectra and SEM picture.4 From the volt-Ampere curve obtained from sandwich cell, when E≤2.2×10~(-1) V·cm~(-1), the room temperature electrical conductivity of BTER and BTER-I_3 were found to be 2.22×10~(-10) s·cm~(-1) and 2.6×10~(-7) S·cm~(-1), respectively.     

One-dimensional Supramolecular Chain Based on a Dinuclear Terbium（Ⅲ） 4-Cyanobenzoate Complex

A new dinuclear Tb（Ⅲ） 4-cyanobenzoate complex [Tb2（4-cba）6（phen）2] （4-Hcba = 4-cyanobenzoic acid and phen = 1,10-phenanthroline） 1 has been synthesized by solvothermal reaction in an ethanol/water mixed solution at 100℃ and structurally characterized by single-crystal X-ray diffraction. Crystallographic data： C72H40N10O12Tb2, Mr=1554.98, triclinic Pi, a = 9.903（3）, b = 11.769（8）, c = 15.078（8）A, a = 111.42（12）, It = 96.37（19）, γ = 101-24（14）°, V= 1572（1）A3, Z= 1, Dc = 1.642 g/cm^3, F（000） = 768 μ = 2.305 mm^-1, the final R = 0.0205 and wR = 0.0543 for 5479 reflections with I 〉 2σ（I）. Structural analysis shows that 1 displays an isolated dinuclear structure. Two eight-coordinated Tb（Ⅲ） ions are bridged by four 4-cba ligands in the syn-syn bidentate coordination mode, and two other 4-cba ligands chelate these two Tb（Ⅲ） ions. The title complex molecules are connected through π-π stacking interactions to generate a one-dimensional supramolecular chain, The characteristic infrared spectra, luminescent properties and thermogravimetric analyses have also been discussed.     

助熔剂对Y3Al5O12：Ce荧光粉性能的影响

在还原气氛下采用高温固相反应法合成了白光LED用黄色荧光粉Y3Al5O12:Ce(YAG:Ce)研究了助熔剂对YAG：Ce荧光粉发光特性的影响，。XRD的测量结果表明加入合适的助熔剂有利于YAG:Ce荧光粉的晶化，并且不引入杂相，选择BaF2和H3BO3同时使用效果要好于单独使用一种助熔剂，助熔剂的加入可增大YAG：Ce荧光粉的激发和发射光谱强度，并能有效降低荧光粉的中心粒径（D50）控制粉体的粒径分布，适用于白光LED的制造。     

溶胶—凝胶合成（Mg,Ca）O—SiO2：Eu^3＋,Bi^3＋发光体及其发光行为

以Ｍｇ（ＮＯ３）２，Ｃａ（ＮＯ３）２，Ｅｕ（ＮＯ３）３，Ｂｉ（ＮＯ３）３和Ｓｉ（ＯＣ２Ｈ５）４为反应物，采用溶胶－凝胶法，在比较低的温度，首次合成０．７０１ｍｏｌＭｇＯ－０．１７５ｍｏｌＣａＯ－１．２５ｍｏｌＳｉＯ２：０．０６ｍｏｌＥｕ＾３＋，０．００２ｍｏｌＢｉ＾３＋（加入Ｌｉ＾＋作为电荷补偿剂）发光体，得到了最佳合成条件，研究了由溶胶向凝胶转变和凝胶向发光晶体的转变过程，探讨了发光体在不同激光     

聚苯胺的化学合成及表征

本工作利用化学方法合成了具有较高电导率的聚苯胺.研究了聚合条件如反应介质的pH值,不同种类的酸及其浓度,氧化剂的用量对聚合的影响.用红外光谱、X-射线衍射、DSC等方法表征了所得的聚合物,并研究了该聚合物的掺杂反应.     

微波合成铝掺杂钻酸锂材料及性能研究

以LiOH·H2O，Al2O3和Co3O4为原料，微波加热合成Li离子电池正极材料LiAlxCo（1-x）O2．通过XRD测试表征了不同Al加入量时合成产物的晶体结构，确定当x≤0．4时，产物为单一相层状结构．计算了不同x时LiAlxCo（1-x）O2的晶胞参数，随着x的增大，a值减小，c值增大．对合成LiAlxCo（1-x）O2样品进行DSC—TGA测试，结果表明，当x不同时，合成样品的热稳定性不同．SEM测试表明，合成晶体粒度较均匀，粒径在5μm左右．电化学测试表明，LiAl0.2Co0.8O2的电化学性能最好，首次循环放电容量为127mAh／g，多次循环容量损失率小于LiCoO2．     

N掺杂可见光化催化剂的研究

The N-doped, yellow colored titanium oxide photocatalysts were prepared with Ti(SO4)2 and NH4HCO3 as precursors by precipitation method. The photocatalytic ability under the irradiation of UV or visible light for the catalysts prepared was studied by degradation of styphnic acid. The materials were characterized by EDS, XRD, FTIR, UV-Vis DRS, and XPS. The results indicate that the photocatalytic ability of catalysts is improved, especially the ability of visible light response. The results of UV-Vis DRS show that the response wavelength range of N-dopped nitrogen is red shifted, the absorption region is expanded to 476 nm.