锗硅酸盐中Mn^2＋的发光性质研究

合成了组成的为（Ｚｎ，Ｍｇ）２（Ｓｉ，Ｇｅ）Ｏ４：Ｍｎ＾２＋的绿色荧光材料，在紫外光激发下有较强的５３２ｎｍ发射。低浓度镁能增强５３２ｎｍ发射，高浓度镁却能抑制５３２ｎｍ发射，而增强６３１ｎｍ红光发射。探讨了Ｍｎ＾２＋的发光性质与基质的晶体结构及组成的关系，计算了Ｍｎ＾２＋离子能级和晶体场参数。     

The spectroscopic properties of Dy3+and Eu3+ co-doped Y3Al5O12 (YAG) phosphors for white LED

Tunable full color emissive Y32.94-xAl5O12: 0.06 Dy3+, xEu3+(YAG: 0.06 Dy, xEu) phosphors with emission peaks at 483 nm(blue), 582 nm(yellow) and 610 nm(red) were synthesized by a sol–gel method. The as-synthesized phosphors were characterized by X-ray powder diffraction(XRD), transmission electron microscopy(TEM), photoluminescence decay lifetimes, photoluminescence excitation and emission spectra. The results showed that photoluminescence intensity varied with excitation wavelength and the doping concentration of Eu3+. The co-doping with Eu3+ compensated the red emission component of the YAG: Dy3+ phosphor. The chromaticity coordinate of YAG: 0.06 Dy, 0.09 Eu phosphor(0.3263, 0.3334) was very close to that of the ideal white light(0.3333, 0.3333). Thus, the YAG: 0.06 Dy, 0.09 Eu phosphor can find potential application in simulating the sunlight artificially through fabricating white light emitters.     

Energy transfer process between Eu3+ and wide-band-gap SnO2 nanocrystals in silica films studied by photoluminescence excitation and time-resolved photoluminescence techniques

Eu3+ions embedded in silica thin films codoped with SnO2 nanocrystals were fabricated by sol–gel and spin-coating methods.SnO2 nanocrystals with controllable sizes were synthesized through precisely controlling the Sn concentrations.The influences of doping and annealing conditions on the photoluminescence intensity from SnO2 nanocrystals are systematically investigated.The effective energy transfer from the defect states of SnO2nanocrystals to nearby Eu3+ions has revealed by the selective photoluminescence excitation spectra.The efficiency of the Forster resonance energy transfer is evaluated by the time-resolved photoluminescence measurements,which is about 29.1%based on the lifetime tests of the SnO2emission.     

浅谈发光微生物

自然界很多生物发光现象来源于发光微生物。发光微生物是一类在正常的生理条件下能够发射可见荧光的微生物．主要分布在海洋环境中。发光微生物在环境监测等领域中具有广泛的应用价值。本文综述常见的微生物（主要是发光菌）发光现象,发光微生物的特征及其应用。     

氯磷酸锶镧中Eu^2＋的发光

合成了La_xSr_(10-2x)Na_x(PO_4)_6Cl_2一系列样品。用X-射线衍射分析测定了它们的相关系和晶胞参数。实验表明在x<2.0区域内为单相区。这些样品的热稳定性好,不吸收360～700nm辐射。发光光谱研究表明Eu~(2+)在该基质中可以形成两种不同的发光中心Eu(Ⅰ)和Eu(Ⅱ),和这两个发光中心的发射峰强度最大值所对应的Eu~(3+)的浓度分别为0.04和0.05mol/mol基质。文中对发射峰值随温度改变而移位的现象作了简要的解释。     

SiO2@TiO2:Eu3+核壳微球的合成、表征及发光性能研究

本文以钛酸四丁酯(Ti(OBu)₄)为钛源合成了SiO₂@TiO₂:Eu₃₊微米核壳微球,采用XRD、EDX、TG-DTA、SEM、TEM和PL等测试手段对其形貌、晶体结构和发光性质进行了表征,对SiO₂@TiO₂:Eu₃₊微米核壳微球形成过程进行了深入的探讨。结果显示,在溶剂热条件下,TiO₂:Eu₃₊纳米粒子层成功的包覆在了SiO₂球的表面,并且在500℃煅烧的条件下由无定型状态转变成了锐钛矿晶相。此外,在紫外光激发下,SiO₂@TiO₂:Eu₃₊具有非常强的红光(Eu₃₊, ₅D₀ → ₇F₂)发射。     

基于5-氨基-2,4,6-三碘基间苯二甲酸和双咪唑混配体体系金属有机骨架化合物的合成、结构与性质研究

在溶剂热条件下,利用Cd(II)、Ni(II)在混配体体系下合成出2个结构新颖的金属有机骨架化合物[Cd(bmimb)(idphate)](1),[Ni_2(bibp)_3(idphate)_2(H_2O)4_]·8H_2O{H_2bmimb=1,4-二[(2-二甲基咪唑)亚甲基]苯,H_2bibp=3,5-二甲基-1,4-二咪唑,idphate=5-氨基-2,4,6-三碘基间苯二甲酸}(2),并通过单晶X射线衍射、红外光谱、热重分析等对这两种化合物进行了表征。结果表明,化合物(1)中,idphate采用双齿螯合的配位模式,bmimb分子采用桥连配位模式,与金属Cd连接形成三维超分子骨架;化合物(2)中,idphate只有一个羧酸基团采用了单齿配位的模式,另外一个羧酸基团悬挂在二维层外未参与配位,二维层通过分子间的弱作用连接的三维有序晶态结构。另外对化合物(1)的进行了荧光光谱分析,该化合物表现出良好的荧光性质。