钛配合物/氧化石墨烯复合储氢材料的制备及其性能研究

文章提出了一种"盆栽"型的钛配合物/氧化石墨烯复合储氢材料模型,以层状石墨为原料制备出高氧化程度的氧化石墨烯,探讨用氧化石墨烯来担载过氟钛酸铵进行储氢性能的可行性。氟钛酸铵/氧化石墨烯复合材料在333 K、453 K和573 K活化1 h后,在77 K,1.2 Mpa时储氢量分别为1.4 wt%、1.2 wt%和2.6 wt%。     

低对称性SiO2/Ag核壳复合纳米结构的银镜反应制备及表面增强拉曼散射活性研究

利用银镜反应在自组装的SiO2纳米粒子单层膜上制备了低对称性的SiO2/Ag核壳复合纳米结构.通过透射电镜(TEM)、扫描电镜(SEM)和紫外-可见分光光度计(UV-Vis)对核壳复合纳米结构的表面形貌和光学性质进行了表征.以亚甲基蓝作为探针分子,研究了低对称性SiO2/Ag核壳复合纳米结构的表面增强拉曼散射(SERS)活性.     

Preparation and characterization of flower-like SrAl2O4:Eu2+,Dy3+ phosphors by sol-gel process

A flower-like Eu2+ and Dy3+ co-doped SrAl2O4 long-lasting phosphorescent (LLP) phosphor was synthesized via the inorganic- salt-based sol-gel method.The crystal structure,morphology and optical properties of the composite were characterized.X-ray diffraction diffu-sion (XRD) data and DSC-TG curves of the phosphor revealed that the SrAl2O4 crystallites have been formed after the precursor was calcined at 900 °C and to be single-phase SrAl2O4 at 1100 °C.The SEM photographs indicated that the sample exhibited ...     

Synthesis and characterization of Y_2O_2S:Eu~(3+),Mg~(2+),Ti~(4+) nanorods via a solvothermal routine

Y2O2S:Eu3+,Mg2+,Ti4+ nanorods were prepared by a solvothermal procedure.Rod-like Y(OH)3 was firstly synthesized by hydrothermal method to serve as the precursor.Y2O2S:Eu3+,Mg2+,Ti4+ powders were obtained by calcinating the precursor at CS2 atmosphere.The Y2O2S:Eu3+,Mg2+,Ti4+ phosphor with diameters of 30-50 nm and lengths up to 200-400 nm inherited the rod-like shape from the precursor after calcined at CS2 atmosphere.The Y2O2S:Eu3+,Mg2+,Ti4+ nanorods showed hexagonal pure phase,good dispersion and exhibite...     

Synthesis and characterization of needle-like BaAleO4：Eu,Dy phosphor via hydrothermal-homogeneous precipitation method

A needle-like Eu2+ and Dy3+ co-doped BaAl2O4 long-lasting phosphor was synthesized via a hydrothermal-homogeneous precipitation method assisted by cetyl trimethyl ammonium bromide(CTAB) as a template.The crystal structure,morphology and optical properties of the composites were characterized.XRD results showed that the single-phase BaAl2O4 was formed at 900 ℃ in an active carbon atmosphere,which was much lower than that prepared by traditional solid-state reaction method.Scanning electron microscopy(SEM) and transmission electron microscopy(TEM) observation revealed that the precursor had well-dispersed distribution and showed needle-like morphology with the average diameter of about 100 nm and the length up to 1 μm.The final product,BaAl2O4:Eu2+,Dy3+ phosphor,inherited the needle-like shape from precursor via adding the surfactant CTAB.After irradiation by ultraviolet radiation with 355 nm for 5 min,the phosphors emitted bluish green color long-lasting phosphorescence corresponding to the typical emission of Eu2+ ion.Both the photoluminescence spectra and luminance decay revealed that the phosphor had efficient luminescent and long-lasting properties.     

LUMINESCENCE CENTERS OF Eu~(2 ) IN KCaF_3:Eu~(2 )

The nature of the emission center of Eu~(2 ) in KCaF_3:Eu~(2 ) strongly depends on the preparative condi-tions.Experimental results show that there are two different d→f transition emission bands,and the origin ofthese two emission bands,their interrelationship and the effect of doping concentration on them have been dis-cussed.A Eu~(2 )-Eu~(3 ) valency change process has been proposed.     

Gd2O2S：Ti的长余辉性能研究及机理探讨

利用高温固相法合成了一种长余辉发光材料Gd2O2S：Ti，利用XRD测试了其结构并测试了其在紫外光激发下的发光特性；停止照射，有橙色的余辉，时间接近2h。分析该磷光体的发光和余辉产生细节，认为空穴和电子的复合导致Ti^3＋的^2E→^2T2的跃迁是产生发光和余辉的原因；并根据缺陷和空位对Gd2O2S：Ti的余辉机理进行探讨，提出了余辉机理模型。     

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。     

硼铝酸锶长余辉发光玻璃的制备及发光性能研究

采用一步合成法制备了硼铝酸锶长余辉发光玻璃,系统研究了热处理温度、热处理时间、冷却制度等条件对长余辉玻璃发光性能的影响.结果表明:在N2气氛下,热处理温度为1300℃、保温时间为3h、试样随炉冷却的制备工艺可得到发光性能优良的长余辉玻璃,该玻璃的长余辉特性源自在玻璃基体中均匀分布的Eu2 、Dy3 共掺杂的SrAl2O4微晶.