Preparation and characterization of layered compound zirconium bis(monohydrogenphosphate)intercalated with rare earth complex

Layered compound zirconium bis(monohydrogenphosphate)(alpha-ZrP) intercalated with rare earth complex Eu(DBM)(3)phen was prepared. The pre-intercalation of p-methoxyaniline into alpha-ZrP makes the interlayer separation large enough to exchange PMA with europium complex, thus, the luminescent assembly was prepared. This was confirmed by X-ray diffraction, UV-visible spectra and elemental analysis. The fluorescence spectra and lifetime of the assembly were also presented.

A comparative study on the electroluminescence properties of some terbium beta-diketonate complexes

By comparing the phosphorescence spectra of Gd(acac)(3) (acac=acetylacetone), Gd(TFacac)3 (TFacac=1,1,1-trifluoroacetylacetone), the effects of fluorine replacement of hydrogen on the triplet state energy of the ligands were revealed. Fluorine can lower the triplet state energy of Hacac and make it more suitable for energy transfer towards the D-5(4) state of terbium. Organic electroluminescent devices (OELDs) with the corresponding trivalent terbium complexes as emissive layers were fabricated. Triple-layer-type devices with a structure of glass substrate/ITO (indium tin oxide)/PVK [poly(N-vinylcarbazole)]/PVK : Tb complex: PBD [2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole]/PBD/Al exhibit bright green luminescence upon applying a dc voltage. The luminance of a device with Tb(TFacac)(3)phen (1,10-phenanthroline) and Tb( TFacac) 3 as emissive layer is higher than that of the corresponding devices with Tb(acac)(3)(phen) and Tb(acac)(3) as emissive layers. The EL device with Tb(TFacac)(3)(phen) as emitter exhibits characteristic emission of Tb3+ ions with a maximum luminance of 58 cd m(-2) at 25 V.

Preparation, characterization and luminescent properties of MCM-41 type materials impregnated with rare earth complex

Hybrid materials incorporating Eu-(TTA)(3). 2H(2)O (7hereafter designated as Eu-TTA, with TTA: thenoyltrifluoroacetone) in unmodified or modified MCM-41 by 3-aminopropyl-triethoxysilane (APTES) were prepared by impregnation method. The obtained materials were characterized using X-ray diffraction (XRD), IR and diffuse reflectance spectroscopy and luminescence spectra. All the hybrid samples exhibited the characteristic emission bands of EU3+ under UV light excitation at room temperature, and the excitation spectra showed significant blue-shifts compared to the pure rare-earth complex. Although the red emission intensity in the modified hybrid was almost the half of the red emission intensity in the pure Eu-TTA complex at room temperature, the hybrid showed a much higher thermal stability due to the shielding character of the MCM-41 host.

Bright green organic electroluminescent devices based on a novel thermally stable terbium complex

A navel thermally stable terbium carboxylate complex, Tb(MTP)(3)(phen) (MTP=monotetradecyl phthalate, phen=1,10-phehanthroline), was synthesized and characterized. The device structure of glass substrate/indium-tin-oxide/poly(p-phenylenevinylene) (PPV)/poly (N-vinycarbazole) (PVK):Tb(MTP)(3)(phen): 1,3,4-oxadizole derivative (PBD)/tris(8-hydroxyquinoline) (Alq(3))/aluminum (Al) was employed to study the electroluminescent properties of Tb(MTP)(3)(phen). A green emission with extremely sharp spectral band of less than 10 nm at 544 nm peak wavelength was observed. A maximum luminance of 152 cd/m(2) and an external quantum efficiency of 0.017% were achieved at a drive voltage of 24 V. A possible mechanism of energy transfer based on the polymer doped with lanthanide organic complex was also proposed.

Luminescence properties of rare-earth (Eu3+ and Tb3+) complexes with paraaminobenzoic acid and 1,10-phenanthroline incorporated into a silica matrix by sol-gel method

Ternary complexes of europium and terbium with paraaminobenzoic acid and 1,10-phenanthroline (Eu(p-ABA)(3). phen . 2H(2)O and Tb(p-ABA)(3). phen . 2H(2)O, where p-HABA = paraaminobenzoic acid and phen = 1,10-phenanthroline) were introduced into a silica matrix by sol-gel method. The luminescence behavior of the complexes in silica gels was studied in comparison with the. corresponding solid-state complexes by means of emission, excitation spectra, and Lifetimes. Within the range of effective dopant concentrations, the luminescence intensities of rare-earth complexes in silica gel increase with the increasing of their dopant concentration. The lifetimes of rare-earth ions (Eu3+ and-Tb3+) in silica gel doped with europium and terbium complexes become longer than those in pure complexes. Very small amounts of rare-earth complexes doped in silica gel matrix can exhibit excellent luminescence properties, (C) 1998 Elsevier Science Ltd.

Luminescence properties of sol-gel derived silica gels doped and undoped with RE-complexes (RE=Eu, Tb)

The luminescence properties of silica gels and silica gels doped with two rare earth complexes, Eu(TTA)(3) and Tb(o-CBA)(3) (TTA=thenoyltriffuocetate, o-CBA=o-chlorobenzoic acid) are reported and discussed. Pure silica gels show a blue luminescence, and the maximum excitation and emission wavelengths depend strongly on the solvents used. Both of the studied rare earth complexes exhibit the characteristic emissions of the rare earth ions in silica gels, i.e., Eu3+5D0-->F-7(J)(J=0,1,2,3,4), Tb3+5D4-->F-7(J)(J=3,4,5,6) transitions. Compared with the pure RE-complexes powder, the silica gels doped with RE-complexes show fewer emission lines of the rare earth ions. Furthermore the rare earth ion (Tb3+) presents a longer lifetime (1346 mu s) in silica gel doped with Tb(o-CBA)3 than in pure Tb((o-CBA)(3) powder (744 mu s). The reasons responsible for these results are discussed in the context.

Luminescence properties of the ternary rare earth complexes with beta-diketones and 1,10-phenanthroline incorporated in silica matrix by a sol-gel method

Ternary complexes of rare earth Eu(dbm)(3).phen and Tb(acac)(3).phen (dbm = dibenzoylmethanide, acac = acetylacetone and phen = 1,10-phenanthroline) were introduced into silica gel by the sol-gel method. The result indicated that the rare earth ions (EU3+ and Tb3+) showed fewer emission lines and slightly lower emission intensities in the silica gel than in the pure rare earth complexes. The lifetimes of rare earth ions in silica gel (Eu3+ and Tb3+) doped with Eu(dbm)(3).phen and Tb(acac)(3).phen were longer than those in purl Eu(dbm)(3).phen and Tb(acac)(3).phen. A very small amount of rare earth complexes doped in a silica gel matrix can retain excellent luminescence properties. (C) 1997 Elsevier Science S.A.

以1-苯基-3-甲基-4-苯甲酰基代吡唑酮[5]萃取稀土和钍铀钛锆及其在分析化学中的某些应用

本文研究了以PMBP-苯萃取稀土和钍、铀、钛、锆的萃取行为。测定了La、Ce、Pr、Nd、Sm、Gd、Dy、Yb、Y、U(Ⅵ)、Ti、Th和Zr的pH_(1/2)值,计算了它们的萃取平衡常数。并介绍了近十年来作者将此萃取剂应用于铀、钍、稀土、鋰、钢铁合金及岩石中痕量稀土、钍和钙的分离和测定方面的工作。实践证明,PMOP合成简便、价格低廉、萃取能力较强,是比TTA更为优越的萃取剂。

稀土(Er, Nd, Yb, Pr, Ho, Sm)有机/无机杂化材料的制备及发光性能研究

目前，国内外对于铕和铽等稀土配合物的可见区发光和应用都有大量研究，但对具有近红外发光（800-1700 nm）性能的稀土配合物的研究还处于起步阶段。由于稀土的近红外发光在光纤通讯、激光系统及诊断学等方面应用具有特殊的优点，越来越引起人们的兴趣和重视。 稀土近红外发光配合物的致命弱点是其光、热和化学稳定性较差，从而限制了其在很多领域的实际应用。而溶胶－凝胶材料和介孔材料具有良好的光、热和化学稳定性，能改善客体分子的结构环境和化学微环境，从而能有效提高客体分子的发光性能。因此，本论文将具有优良近红外发光性能的稀土配合物分别与上述两种基质复合，从实验和理论研究稀土近红外发光杂化材料的性能和应用价值，制备出具有良好稳定性的高效稀土近红外发光杂化材料，以期为光纤通讯、激光等领域提供潜在的候选材料。围绕这一宗旨，开展了如下工作： 通过原位技术分别得到了掺杂和嫁接[Ln(dbm)3phen]化合物（Ln = Er, Nd, Yb）的杂化凝胶材料，Ln-D-P gel和Xerogel-Ln。通过对其近红外发光性能的研究，表明材料中配体能很好的保护稀土离子，并将能量有效的传递给稀土离子。采用Judd-Ofelt理论对所得部分材料进行了光谱分析，基于实验数据和理论分析表明其具有潜在的光放大和激光应用价值。 选择了两种含全氟化烷基链的β-二酮配体Hhfth和Htfnb，通过功能化的phen-Si配体，将三元配合物[Ln(hfth)3phen] (Ln = Er, Nd, Yb, Sm)和[Pr(tfnb)3phen]成功共价嫁接到介孔MCM-41和SBA-15杂化材料中，得到的衍生材料Ln(hfth)3phen–MCM-41、Pr(tfnb)3phen–MCM-41和Ln(hfth)3phen–SBA-15、Pr(tfnb)3phen–SBA-15都保持了高度有序的介孔p6mm结构，并展现出稀土离子特征的近红外发射。所得稀土配合物功能化的材料的发射光谱能完全覆盖对光通讯极具应用价值的1300-1600nm区域。 通过对Er(dbm)3phen–M41(X, Y) (X = 1~14, Y = 3, 6, 12, 18, 24 h)材料系统的比较研究，选择了X = 12, Y = 6作为合成目标材料的优化参数，通过功能化的phen-Si配体将[Ln(dbm)3phen]配合物共价嫁接于有序介孔MCM-41和SBA-15中(Ln = Er, Nd, Yb)，所得两类材料Ln(dbm)3phenM41和Ln(dbm)3phenS15都保持了很好的介孔有序性，并具有良好的近红外发光性能。通过对Ln(dbm)3phenM41和Ln(dbm)3phenS15两类材料发光行为的比较，以及两类材料中稀土离子的含量及孔结构的分析，推出以SBA-15为载体得到的材料在相对发光强度和荧光寿命上，均比以MCM-41为载体的材料有所提高。 通过对8－羟基喹啉配体进行改性，合成了具有双功能的配体Q-Si，继而合成了共价嫁接8－羟基喹啉衍生物的介孔杂化材料Q–SBA-15，其形貌均一，并具有高度有序的介孔p6mm结构。通过配体交换反应，得到了嫁接稀土喹啉配合物的具有近红外发光性能的介孔杂化材料LnQ3–SBA-15 (Ln = Er, Nd, Yb)，其仍然保持高度有序的介孔结构，且外形呈现与母体材料Q–SBA-15相似的弯曲圆柱状。激发配体的吸收，LnQ3–SBA-15材料都分别展现出相应稀土离子特征的近红外发射，并详细分析和讨论了所得介孔杂化材料的近红外发光性能。

M_2RSbO_6:R~(3+)复合氧化物的合成组成结构和性能的研究(M = Ba、Sr、Ca, R = La、Gd、Y、Bi, R' = Sm、Eu、Dy、Ho、Er、Tm)

对于稀土与非稀土所组成的二元复合氧化物的研究国外已有较多的报导。但是，对于稀土和锑的复合氧化物只是近年来才开始有些研究工作。含锑与稀土的多元复合氧化物的报导就更少。本文在我们实验室张静筠等人三元复合氧化物研究的基础上，开展Mo—Sb_2O_5—R_2O_3—R'_2O_3—Bi_2O_3多元体系的研究工作，这对于我国丰产元素稀土和锑的应用以及利用Bi~(3+)的激活与敏化将是有益的。本文按Thornton等人的方法合成了Ba_2BiSbO_6，Ba_2GdSbO_6，按EγΦECEHKO等人的方法合成了M_2RSbO_6 (M = Ba、Sr、Ca, R = La Y)。并以M_2RSbO_6为基质，掺Sm~(3+)、Eu~(3+)、Dy~(3+)、Ho~(3+)、Er~(3+)、Tm~(3+)和Bi~(3+)，研究它们的化学组成，晶体结构与发光性能的关系及规律，Bi~(3+)的荧光和敏作用。同时研究了它们的磁学和热学性能。化学组成的分析结果表明，计算的含量与实验测得的含量符合较好，说明化学反应是按化学计量比进行的。通过X-射线粉沫物相分析和晶胞参数的理论计算确定M_2RSbO_6(M = Ba、Sr、R = La、Y、Gd、Bi)复合氧化物是属于立方钙钛太型化合物。空间群为Fm3m，点群为Oh。用计算机计算了Ca_2YSbO_6的晶胞参数并结合荧光光谱分析确定它属于畸变的单斜钙钛矿，空间群为P_(21)。用磁天平测量了样品M_2RSbO_6 (M = Ba、Sr、Ca; R = Gd、Y、Bi)的磁化率。除Ba_2GdSbO_6是顺磁性物质外共余的都是反磁性的物质。按所用原料Sb_2O_5计算的磁化率与测量值符合较好，表明在所研究的M_2RSbO_6化合物中锑是正五价的。用热重热差分析仪测量了样品在反应中的热性能，观察到在化合物形成的过程中所用原料Sb_2O_3大约在520 ℃左右氧化变为Sb_2O_5。除所用原料碳酸盐分解外没有挥发性的物质，这就进一步证明化学组成分析和磁化率测量的结果是正确的。光学测量的结果表明，所有的磷光体随着激活离子浓度的不同其光谱都发生规律性的变化。对于不同Eu~(3+)浓度的Ba_2YSbO_6:Eu~(3+)和Br_2YSbO_6:Eu~(3+), Bi~(3+)体系用254nm激发时均能观察到Eu~(3+)于595nm的尖峰发射。用基质和Bi~(3+)的激发峰325nm激发时，明显地看到敏化剂Bi~(3+)到Eu~(3+)的能量传递，使Eu~(3+)于595nm的发射大大增强，我们认为Bi~(3+)对Eu~(3+)的敏化作用是由于基质和Bi~(3+)的~1S。→ 3P_1的跃迁吸收了激发的能量，然后无辐射弛豫到Eu~(3+)的激发态~5D_0，产生~5D_0 → 7F_1的磁偶极跃迁。对于不同Eu~(3+)浓度的Sr_2YSbO_6:Eu~(3+)和Sr_2YSbO_6:Eu~(3+), Bi~(3+)体系用245nm激发时均能观察到Eu~(3+)于595nm的尖峰发射。用基质和Bi~(3+)的激发峰335nm激发时，观察到基质和Bi~(3+)对Eu~(3+)具有某种能量传递。敏化作用机理与上述的Ba_2YSbO_6:Eu~(3+)和Ba_2YSbO_6:Eu~(3+), Bi~(3+)体系相同。对于不同Eu~(3+)浓度的Ca_2YSbO_6:Eu~(3+)和Ca_2YSbO_6:Eu~(3+), Bi~(3+)体系用396nm激发时，均能观察到Eu~(3+)于613nm很强的尖峰发射。用基质和Bi~(3+)的激发峰313nm激发时，见到Bi~(3+)和基质对Eu~(3+)具有某种能量传递，这种敏化作用主要是由于基质和Bi~(3+)的3P_1 → ~1S_0的400nm的宽带发射和Eu~(3+)的~7F_0 → ~5L_6的396nm的吸收相匹配产生~5L_6→~5D_0→~7F_2的跃迁。通过对激发光谱和荧光光谱的分析给出了Ca_2Y_(0.96)Eu_(0.04)SbO_6的能级图，从实验上可见，Eu~(3+)的发光强烈地依赖于钙钛矿的结构，当Eu~(3+)在空间群为Fm3m 的Ba_2YSbO_6和Sr_2YSbO_6中处于Oh点对称性时，主要是~5D_0 → ~7F_1的磁偶极跃迁。当Eu~(3+)在空间群为P_(21)的单斜钙钛矿中时，主要是~5D_0 → ~7F_2的电偶极跃迁。对于不同掺杂浓度M_2YSbO_6:R~(13+)(M = Ba、Ca; R' = Sm、Dy、Ho、Er、Tm)体系，通过激发和荧光光谱的研究，合理地确定了谱项。发现基质对Sm~(3+)、Dy~(3+)、Ho~(3+)具有敏化作用。对不同Bi~(3+)浓度的Ca_2YSbO_6:Bi~(3+)，由激发和荧光光谱可见Bi~(3+)具有二个激发带，第一激发带位于240nm处相当于~1S_0 → ~1P_1的跃迁，第二激发带位于315nm处相当于~1S_0 → ~3P_1的跃迁。有一个很强的兰紫色发射位于400nm处相当于~3P_1 →~1S_0的跃迁。

Uniform YVO4:Ln(3+) (Ln = Eu, Dy, and Sm) nanocrystals: Solvothermal synthesis and luminescence properties

Well-dispersed YVO4:Ln(3+) (Ln = Eu, Dy, and Sm) nanocrystals with uniform morphology and size have been synthesized via a facile solvothermal route. XRD results demonstrate that all of the three samples can be well indexed to the pure tetragonal phase Of YVO4, indicating that the Eu3+, Dy3+, and Sm3+ have been effectively doped into the host lattices of YVO4. TEM images show that the YVO4 nanocrystals exhibit ellipsoid shape and a mean size of about 20 nm, which is in good agreement with the estimation of XRD results.

Uniform Ln(OH)(3) and Ln(2)O(3) (Ln = Eu, Sm) Submicrospindles: Facile Synthesis and Characterization

Monodisperse hexagonal Ln(OH)(3) (Ln = Eu, Sm) submicrospindles with uniform morphology and size have been Successfully synthesized in a large scale via a Facile aqueous solution route from the mixture of aqueous solutions or LnCl(3) and NaOH at 5 degrees C without using any surfactant or template. The as-synthesized products are characterized by X-ray diffraction (XRD), thermogravimetric analysis (TGA), energy-dispersive X-ray (EDX) spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). The SEM and TEM images show that the as-formed Ln(OH)(3) samples have a spindlelike shape with an equatorial diameter of 80-200 nm and a length of 500-900 nm, which are aggregates of even smaller nanoparticles.

Synthesis and characterization of monodisperse spherical SiO2@RE2O3 (RE = rare earth elements) and SiO2@Gd2O3:Ln(3+) (Ln = Eu, Tb, Dy, Sm, Er, Ho) particles with core-shell structure

Spherical SiO2 particles have been coated with rare earth oxide layers by a Pechini sol-gel process, leading to the formation of core-shell structured SiO2@RE2O3 (RE = rare earth elements) and SiO2@Gd2O3:Ln(3+) (Ln = Eu, Tb, Dy, Sm, Er, Ho) particles. X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), photoluminescence (PL), and cathodoluminescence spectra as well as lifetimes were used to characterize the resulting SiO2@RE2O3 (RE = rare earth elements) and SiO2@Gd2O3:Ln(3+) (Eu3+, Tb3+, Dy3+, Sm3+, Er3+, Ho3+) samples. The obtained core-shell phosphors have perfect spherical shape with narrow size distribution (average size ca. 380 nm), smooth surface and non-agglomeration. The thickness of shells could be easily controlled by changing the number of deposition cycles (40 nm for two deposition cycles).

Self-assembled 3D flowerlike Lu2O3 and Lu2O3 : Ln(3+) (Ln = Eu, Tb, Dy, Pr, Sm, Er, Ho, Tm) microarchitectures: Ethylene glycol-mediated hydrothermal synthesis and luminescent properties

Three-dimensional flowerlike Lu2O3 and Lu2O3:Ln(3+) (Ln = Eu, Th, Dy, Pr, Sm, Er, Ho, Tm) microarchitectures have been successfully synthesized via ethylene glycol (EG)-mediated hydrothermal method followed by a subsequent heat treatment process. X-ray diffraction, Fourier transform infrared spectroscopy, energy-dispersive X-ray spectra, thermogravimetric and differential thermal analysis, elemental analysis, inductively coupled plasma atomic absorption spectrometric analysis, ion chromatogram analysis, X-ray photoelectron spectra, scanning electron microscopy, transmission electron microscopy, photoluminescence spectra as well kinetic decays, and cathodoluminescence spectra were used to characterize the samples. Hydrothermal temperature, EG, and CH3COONa play critical roles in the formation of the lutetium oxide precursor microflowers. The reaction mechanism and the self-assembly evolution process have been proposed. The as-formed lutetium oxide precursor could transform to Lu2O3 With their original flowerlike morphology and slight shrinkage in the size after postannealing process.

Uniform Lanthanide Orthoborates LnBO(3) (Ln = Gd, Nd, Sm, Eu, Tb, and Dy) Microplates: General Synthesis and Luminescence Properties

A variety of uniform lanthanide orthoborates LnBO(3) (Ln = Gd, Nd, Sm, Eu, Tb, and Dy) microplates have been successfully prepared by a general and facile conversion method. One-dimensional (ID) lanthanide hydroxides were first prepared through a simple hydrothermal process. Subsequently, uniform LnBO(3) microplates were synthesized at the expense of the ID precursors during a hydrothermal conversion process. The whole process in this method was carried out in aqueous condition without the use of any organic solvents, surfactant, or catalyst. The as-obtained rare earth ions doped GdBO3 and TbBO3 microplates show strong light emissions with different colors coming from different activator ions under ultraviolet excitation or low-voltage electron beam excitation, which might find potential applications in fields such as light phosphor powders and advanced flat panel display devices.