Photoluminescence and electroluminescence properties of a samarium complex Sm(TTA)(3)phen

The photoluminescence (PL) and electroluminescence (EL) properties of a samarium complex Sm(TTA)(3)phen (TTA = 2-thenoyltri-fluoroacetonate, phen = 1, 10-phenanthroline) were investigated. The results show that Sm(TTA)3phen could be used as promising luminescent and electron transporting material in the electroluminescent devices. The difference between PL and EL spectra was noticed and discussed. Besides, it is noteworthy that the choice of the hole transporting layer (HTL) showed significant effect on the device performance, which was explained by the low-lying highest occupied molecular orbit (HOMO) level of Sm(TTA)3phen and the different hole injection barrier at the HTL/EML (emitting material layer) interface.

Crystal structure of a luminescent complex Sm(HTH)(3)Phen

The crystal structure of Sm(HTH)(3)Phen [HTH: 4,4,5,5,6,6,6-heptafluoro-1-(2-thienyl)-1,3-hexanedione, Phen: 1,10-Phenanthroline] has been determined by single crystal X-ray diffraction and the coordination geometry of Sm atom is a dodecahedron. The complex can give the characteristic luminescence of Sm3+ upon UV excitation.

Preparation and luminescence properties of ormosil material doped with Eu(TTA)(3)phen complex

The europium complex, Eu(TTA)(3)phen (TTA = thenoyltrifluoroacetone, phen = 1,10-phenanthroline) was successfully doped into organically modified silicate (ormosil) matrix-SiO2/(VTMOS+PMMA) (VTMOS = vinyltrimethoxysilane, PMMA = polymethylmethacrylate) via sol-gel process, and the luminescence properties of the resultant ormosil composite phosphors [ormosil: Eu(TTA)(3)phen were investigated compared with those of the pure Eu(TTA)(3)phen complex powder. The ormosil composite materials incorporated with Eu(TTA)(3)phen show the characteristic red emission of Eu3+ ion. The Eu3+ possesses fewer emission lines and longer lifetime in the hybrid phosphor than in the pure Eu(TTA)(3)phen complex. This has been explained from the viewpoint of the surrounding environment where the Eu3+ ion lies. (C) 2000 Elsevier Science B.V. All rights reserved.

Bright red organic electroluminescent devices based on a soluble rare earth complex Eu(TTA)(3) Phen

An Electroluminescent device with PVK film doped with Eu(TTA)(3) Phen and PBD was fabricated. The device structure of glass substrate/indium-tin-oxide/PPV/PVK : Eu(TTA)3 Phen : PBD/Alq(3)/Al was employed. A sharply red electroluminescence with a maximum luminance of 56. 8 cd/m(2) at 48 V was achieved.

Luminescent Langmuir-Blodgett films based on Tiron-terbium

The luminescent ultrathin Langmuir-Blodgett (LB) films containing Tb-2(C6H3S2O8)(2) (Tiron-Tb) were successfully obtained. The modifications of compression isotherms of dimethyldioctadecylammonium bromide (DODA) have been observed when the Tiron-Tb complex was dissolved in the subphase. The effect of Tiron-Tb in the subphase on Langmuir films of DODA has been studied. Low-angle X-ray diffraction result indicates that the LB films have a good periodic layered structure. The UV and IR spectra results show the Tiron-Tb complex is incorporated into LB films layer-by-layer and the LB films are homogeneously deposited. The LB films containing Tiron-Tb can emit strong green luminescence, and the luminescence signal can be detected from a single layer. The luminescence properties of LB films have been discussed compared with those of the solutions.

Structural refinement, optical and electrical properties of Ba1-x Sm-2x/3](Zr0.05Ti0.95)O-3 ceramics

Samarium doped barium zirconate titanate ceramics with general formula Ba1-x Sm-2x/3](Zr0.05Ti0.95)O-3 x = 0, 0.01, 0.02, and 0.03] were prepared by high energy ball milling method. X-ray diffraction patterns and micro-Raman spectroscopy confirmed that these ceramics have a single phase with a tetragonal structure. Rietveld refinement data were employed to model BaO12], SmO12], ZrO6], and TiO6] clusters in the lattice. Scanning electron microscopy shows a reduction in average grain size with the increase of Sm3+ ions into lattice. Temperature-dependent dielectric studies indicate a ferroelectric phase transition and the transition temperature decreases with an increase in Sm3+ ion content. The nature of the transition was investigated by the Curie-Weiss law and it is observed that the diffusivity increases with Sm3+ ion content. The ferroelectric hysteresis loop illustrates that the remnant polarization and coercive field increase with an increase in Sm3+ ions content. Optical properties of the ceramics were studied using ultraviolet-visible diffuse reflectance spectroscopy.

Valence state change and refractive index change induced by femtosecond laser irradiation in Sm3+ doped fluoroaluminate glass

We report femtosecond laser induced valence state and refractive index change in transparent Sin(3+)-doped fluoroaluminate glass. The effect of annealing on the induced changes was studied and the thermal stability of these changes was discussed. The results show that the femtosecond laser induced valence state change is more stable than the induced refractive index change. The observed phenomenon could be applied to design the thermally erasable or stable storage medium. (c) 2007 Elsevier B.V. All rights reserved.

Fe(acac)3/phen/O2体系中苯甲醇的选择氧化

研究了Fe(acac)3/phen/O2在碱(K2CO3和NaOH)体系下对苯甲醇的选择氧化反应.循环伏安实验证实,Fe(acac)3通过碱调节其氧化还原电势可直接活化氧.

Preparation and luminescence properties of ormosil hybrid materials doped with Tb(Tfacac)(3)phen complex via a sol-gel process

In this paper, silica-based transparent organic-inorganic hybrid materials were prepared via the sol-gel process. Tetraethoxysilane (TEOS) and 3-glycidoxypropyltrimethoxysilane (GPTMS) were used as the inorganic and organic precursors, respectively. The terbium complex, Tb(Tfacac)(3)phen (Tfacac = 1,1,1-trifluoroacetylacetone, phen = 1, 10-phenanthroline) was successfully doped into organically modified silicate (ormosil) matrix derived from TEOS and GPTMS, and the luminescent properties of the resultant ormosil composite phosphors [ormosil/Th(Tfacac)(3)phen] were investigated compared with those of the Tb(Tfacac)(3)phen incorporated into SiO2 derived from TEOS (labeled as silica/Tb(Tfacac)(3)phen). Both kinds of the materials show the characteristic green emission of Tb3+ ion. The luminescence behavior of the resultant composite products was dependent on the matrix composition. The optimized lanthanide complex concentration in the ormosil/Tb(Tfacac)(3)phen was increased compared with in silica/Tb(Tfacac)(3)phen. Furthermore, the lifetime of Tb3+ in Tb(Tfacac)(3)phen, silica/Tb(Tfacac)(3)phen and ormosil/Tb(Tfacac)(3)phen follows the sequence: onmosil/Tb(Tfacac)(3)phen>silica/Tb(Tfacac)(3)phen>pure Tb(Tfacac)(3)phen.

Encapsulation of Eu(TTA)(3) into MCM-41 mesoporous molecular sieve by sol-gel method

The rare earth complex Eu(TTA)(3) was successfully encapsulated into MCM-41 mesoporous molecular sieve by the addition of the complex into the sol-gel mixture for the synthesis of MCM-41 mesoporous material under microwave radiation. The as-synthesized MCM-41-hosted Eu(TTA)(3) mesophase was confirmed to possess hexagonally ordered mesostructure and a uniform crystal. size of about 30 nm with XRD and HRTEM techniques. Moreover, the IR spectrum, photoluminescence effect and fluorescence lifetime of the Eu(TTA)(3)/MCM-41 hybrid were also studied. An increase in Stokes' shift and no change in luminescence lifetime were observed to the resultant mesophase in comparison with Eu(TTA)(3) in ethanol solution.

Bright red electroluminescent devices based on a soluble lanthanide complex Eu(DBM)(3)(phen)

Electroluminescent devices with PVK film doped with Eu(DBM)(3)(phen) and PBD were fabricated. The device structure of glass substrate/indium-tin-oxide/PPV/PVK:Eu(DBM)(3)-(phen):PBD/Alq(3)/Al was employed. The emissive layer was formed by spin-casting method. A sharply red electroluminescence with a maximum luminance of 114.4 cd/m(2) was achieved at 42 V.

CRYSTAL-STRUCTURE OF [YB (NO3)3 (PHEN) (H2O)]CENTER-DOT(12-CROWN-4)

The title complex was prepared by reacting Yb(NO3)3 (12-crown-4) with 1, 10-phenanthiroline (hereafter phen) in acetone. It crystallized in the triclinic space group P1BAR with a = 10.095(5), b = 17.415(4), c = 8.710(2) angstrom; alpha = 92.45(2), beta = 115.83(3), gamma = 74.08(3)degrees and D(c), = 1.85 g cm-3; Z = 2. The metal ion in this complex is nine-coordinated to three bidentate nitrate ions, two nitrogen atoms of a phen and a water molecule. The crown ligand is hydrogen bonded to the coordination water molecule. The symmetry change of the crown ether is also discussed.

Calorimetric investigations of luminescent films polycarbonate (PC) doped with europium complex [Eu(TTA)(3)(H(2)O)(2)]

Polymers doped with rare earth complexes are advantaged in film production for many applications in the luminescent field. In this luminescent polycarbonate (PC) films doped with diaquatris(thenoyltrifluoroacetonate)europium(III) complex [Eu(TTA)(3)(H(2)O)(2)] were prepared and their calorimetric and luminescent properties in the solid state are reported. The thermal behavior was investigated by utilization of differential scanning calorimetry (DSC) and thermogravimetry (TG). Due of the addition of rare earth [Eu(TTA)(3)(H(2)O)(2)] into PC matrix, changes were observed in the thermal behavior concerning the glass transition and thermal stability. Characteristic broadened narrow bands arising from the (5)D(0) -> (7)F(J) transitions (J = 4-0) of Eu(3+) ion indicate the incorporation of the Eu(3+) ions in the polymer. The luminescent films show enhancement emission intensity with an increase of rare earth concentration in polymeric matrix accompanied by decrease in thermal stability.

Organosilylated complex [Eu(TTA)3(Bpy-Si)]: A bifunctional moiety for the engeneering of luminescent silica-based nanoparticles for bioimaging

A new highly luminescent europium complex with the formula [Eu(TTA) 3(Bpy-Si)], where TTA stands for the thenoyltrifluoroacetone, (C 4H3S)COCH2COCF3, chelating ligand and Bpy-Si, Bpy-CH2NH(CH2)3Si(OEt)3, is an organosilyldipyridine ligand displaying a triethoxysilyl group as a grafting function has been synthesized and fully characterized. This bifunctional complex has been grafted onto the surface of dense silica nanoparticles (NPs) and on mesoporous silica microparticles as well. The covalent bonding of [Eu(TTA)3(Bpy-Si)] inside uniform Stöber silica nanoparticles was also achieved. The general methodology proposed could be applied to any silica matrix, allowed high grafting ratios that overcome chelate release and the tendency to agglomerate. Luminescent silica-based nanoparticles SiO2-[Eu(TTA)3(Bpy-Si)], with a diameter of 28 ± 2 nm, were successfully tested as a luminescent labels for the imaging of Pseudomonas aeruginosa biofilms. They were also functionalized by a specific monoclonal antibody and subsequently employed for the selective imaging of Escherichia coli bacteria. © 2013 American Chemical Society.