Electroluminescent Property of A Novel Co-Doped Rare Earth Complex

A novel co-doped rare earth complex Gd0.5Eu0.5（TTA）3Dipy was synthesized and chosen as the emitter material in the organic electroluminescent device ITO/PVK：Gd0.5 Eu0.5 （TTA）3Dipy/PBD/A1. It was proved that there was Forster energy transfer from Gd^3＋ to Eu^3＋. The electroluminescent mechanism of the device was proposed by measuring and analyzing the emission and the excitation spectra of the emissive layer. Gd^3＋ might play the role of promoting the en- ergy transfer from PVK to Eu^3＋ and inhibiting an intrinsic luminescence of PVK. The device displayed red light with good monochromaticity. The possible energy transfer process of the device was preliminarily discussed.     

Study of Electroplex Emission from Organic Electroluminescent Devices with Rare Earth Complex

A novel organic electroluminescent device was made with the structure of ITO/PVK：Tb0.5Eu0.5（TTA）3 Dipy/ BCP/Alq3/Al（a） which utilized the rare earth complex Tb0.5Eu0.5（TTA）3 Dipy as the emitting layer. When it was driven under a direct electric field, 612 nm emission from EU^3＋ and 410 nm emission from PVK were observed. In addition, in the EL spectrum a new peak at 490 nm appeared. From the analysis of different devices, the mechanism of the new emission was studied. It was concluded that the new emission was the electroplex originating from the interface between the ligand （TTA）3Dipy and BCP.     

Doped Organic Electroluminescence from a Novel Rare Earth Complex Tb （3-metho） 3 phen

A novel rare earth complex Tb (3-metho)3phen was synthesized and characterized. The complex was doped into PVK to improve the conductivity and film-forming property of Tb(3-metho) 3phen. A device with a structure of ITO/PVK: Tb(3-metho)3phen/Al was fabricated to study the eleetrolumineseent properties of Tb(3-metho) 3 phen. And the optoluminescent and AFM properties of this device were also studied, which proved the existence of energy transfer from PVK to Tb(3-metho)3phen. As a result, a pure green emission with sharp spectral band at 547.5 nm was observed.     

Study on Luminescence Properties of a Novel Rare Earth Complex Eu（ TTA）2 （N-HPA） Phen

A novel rare earth complex Eu（TTA）2（N-HPA）Phen （TTA = thenoyltrifluoroacetone, N-HPA = N-phenylanthranilic acid, and phen = 1,10-phenathroline ）, which contains three different ligands, was synthesized. The Eu complex was blended with poly N-vinylcarbazole （PVK） in different weight ratios and spin coated into films. The luminescence properties of films were investigated and energy transfer between PVK and the complex was discussed. Multilayer structural devices consisting of ITO/PVK： Eu （TTA）2 （N-HPA） phen/BCP/Alq3/Al were fabricated with PVK ： Eu （TTA）2（N-HPA） as light-emitting layer. Increasing the concentration of Eu in the PVK thin film would inhibit the emission of PVK to different degrees. Finally, the pure red luminescence of europium（ Ⅲ ） was observed when the doping weight ratio was approximately 1 ： 5, which indicated an effective energy transfer from PVK to rare earth complex.     

Luminescent Properties of A Novel Terbium Complex Tb（o-BBA）3（phen）

A novel rare earth complex of terbium ion with 2-benzoylbenzoic acid and 1, 10-phenathroline （Tb（o-BBA）3 （phen）, o-BBA-2-benzoylbenzoic acid, phen = 1, 10-phenathroline） was used as an electroluminescent material for the first time. The Tb complex was blended with poly（N-vinylcarbazole） （PVK） in different weight ratios and spinn to coated into films （noted as PVK ：Tb films）. The photoluminescence （PL） properties of films were investigated and the optimum weight ratio between PVK and Tb（o-BBA）3（phen） was found to be 3：1. Monolayer devices with the structure ITO/PVK： Tb/AI were fabricated and emitted green light, which was characteristic of Tb^3＋ emission. The results show that mecha- nisms for PL and EL are different. The PL is considered to be caused because of energy transfer and direct excitation to the Tb（o-BBA）3（phen） molecule, while EL is mainly on charging trapping.     

Cooperative energy transfer in Eu3+,Yb3+ codoped Y2O3 phosphor

Under 980 nm laser excitation,red emission(5D0-7FJ(J=0,1,2)) of Eu3+ was observed in cubic Y2O3 codoped with Eu3+ and Yb3+.The dependence of the upconverted emission on doping concentration and laser power was studied.Yb3+ emission around 1000 nm(2F5/2-2F7/2) was reported upon excitation of Eu3+ ions.The decay curves of 5DJ(J=0,2) emission of Eu3+ under excitation of 266 nm pulse laser were examined to investigate the Eu3+→Yb3+ energy transfer process.Cooperative energy transfer process was discussed as the possible mechanism for the visible up-conversion luminescence of Eu3+ and near-infrared down-conversion emission of Yb3+.     

Preparation and Characterization of Eu／MCM-41 Mesoporous Composite Material

Nanosized mesoporous molecular sieve MCM-41 was synthesized with tetraethyl orthosilicate (TEOS) as the source of silica and cetyltrimethyl-ammonium bromide (CTAB) as the template. The photoluminescent functional supramolecule Eu(DBM)3phen/MCM-41 between the nanosized MCM-41 and Eu(DBM)3phen was prepared in chloroform, and characterized by XRD, HRTEM, IR and fluorescent spectroscopy.     

A Novel Structure of ZnS：Tm^3＋ TFEL Device

A novel ZnS :TmF3 TFEL device with the structure of ITO/SiO2/ZnS : TmF3/SiO2/ZnS : TmF3/SiO2/Al was prepared by e-beam evaporation method. The EL emission spectra show that the brightness of the novel structure devices greatly increases compared with that of devices with traditional double insulator structure, and the ratio of blue emission to red emission of the novel structure device is also improved. The improvement of the EL characteristics of this kind TFEL device is attributed to both of the electron acceleration and the ZnS/SiO2 interface.     

Growth and Spectral Properties of Crystal Er^3＋ ：Y0.5Gd0.5VO4

Er^3＋ ：Y0.5Gd0.5VO4 crystal with good optical quality was grown by Czochraski method. The structure of the crystal was determined by X-ray powder diffraction method. The segregation coefficient of Er^3 ＋ ions in the crystal was measured by the ICP method. The absorption and emission spectra were also measured. On the basis of the spectra, the absorption cross-sections, emission spectrum FWHM and fluorescence lifetime of the crystal were calculated. From the properties mentioned above.     

Preparation and properties of temperature sensitive paint based on Eu(DBM)3phen as probe molecule

Probe molecule Eu(DBM)3 phen is made up of europium oxide(Eu_2 O_3),dibenzoylmethane(DBM) and1,10-phenanthroline(phen). The temperature sensitive paint(TSP) was compounded by the polymerization of the probe molecule, methyl methacrylate(MMA) and the initiator of benzoyl peroxide(BPO).The structure, morphology, luminescence property of probe molecule and the temperature quenching property of the temperature sensitive paint(TSP) were characterized by infrared spectrometer, UV-vis spectrometer, scanning electron microscopy and fluorescence spectrometer respectively. The infrared spectrum and UV-vis spectra show that Eu and DBM form six membered rings, and Eu-O coordinate bonds form. The nanocrystals are in sphere-like morphology with an average size of approximately100 nm. Fluorescence spectra present that the performance of temperature quenching is excellent,what's more, TSP sample has different temperature sensitivity in various temperature scope. Particularly,under excitation of 286 nm, TSP has a highest temperature sensitivity between 50 and 60 ℃, and the strongest fluorescence emission reaches a peak(615 nm). It indicated that probe molecule(Eu(DBM)_3 phen) has strong luminescent intensity and the temperature quenching properties of Eu(DBM)_3 phen/PMMA is good.     

Organic Light-Emitting Device Based on Terbium Complex

Organiclight emittingdevices(OLEDs)have beenattractingconsiderableinterestbecauseoftheir lowdrive voltage,potentialapplicationsinflatpanel displaysincethefirstdouble layerstructuredevice withhighefficiencyandluminancewasfabricatedby TangandVanSlykein1987[…     

Emission Characteristics of PVK Doped TbY（o-MBA）6（phen）2 Systems

Since the pioneering work of Tang and VanSlykeon organic light emitting diodes(OLEDs)in1987,OLEDs have been particularlyinterestedin because oftheir potential applications in next-generationflat-pan-el displays and large-area flexible displays[1~3].Rareearth complex materials have been widely used incathodoluminescent display phosphor screens,lasersand lamps because their photoluminescence PL ex-hibits high quantumefficiencies and very sharp spec-tral bands.Inthe1990s,Kido et al[4~6]first…     

Luminescence Characteristic of a New Novel Coprecipitate Rare Earth Complexes

Organicelectroluminescence (OEL)hasbeenex tensivelystudiedbecauseoftheirpotentialapplicationinflatpaneldisplayssincethefirsttwo layerOELde vicewithhighefficiencyandluminancewasfabricatedin 1987[1～ 3] .Rareearth (RE)metalcomplexeshavesomegoodcharacteristics ,suchasextremelynarrowe missionbandsandhighinternalquantumefficiencies ,whicharesuitableforuseastheemissionmaterialsinOEL[4 ] .Tb3+complexwasfirstintroducedintoOELdevices ,andsharpgreenemissionfromTb3+ionhasbeenobserved[5] .Sincethen …     

Organic Light Emitting Devices Based on Terbium Complex

Rare earth complex Tb(BA)3phen was synthesized, which is first used as an emitting material in electroluminescence. The properties of monolayer device with the swing film rate of 1000 r·min-1(70 nm) and the weight ratio of 1:5(PVK:Tb(BA)3phen) are the best. And the highest brightness of this device reached 26.8 cd·cm-2 at a fixed bias of 21 V. Bright green emission could be obtained from the optimized double-layer device and the highest EL brightness of the device reached 322 cd·m-2 at the voltage of 22 V.     

Synthesis, Characterization and Fluorescence Properties of Europium, Terbium Complexes with Biphenyl-4-Carboxylic Acid and o-Phenanthroline

Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indicate that the complexes have the composition of Eu(phen)L3·1/2H2O, Eu0.5RE0.5(phen)L3·1/2H2O; Tb(phen)L3·H2O and Tb0.5RE0.5(Phen)L3·1/2H2O. (RE=Y3 , La3 and Gd3 ; L=biphenyl 4-carboxylic acid; phen=o-Phenanthroline). The studies of their IR, UV 1H NMR and molar conductivities demonstrate that biphenyl 4-carboylic acid is bounded with RE(Ⅲ) ion. Rare earth ions coordinate with two nitrogen atoms of phen molecules directly in these rare earth complexes. The fluorescence spectra and fluorescence lifetimes of the rare earth complexes show that the fluorescent intensity and lifetime of a series of europium complexes are longer than those of the series of terbium complexes as having the some ligands. There are better fluorescent intensity and lifetime of hetero-nuclear rare earth complexes than homo-nuclear rare earth complexes for europium complexes. The fluorescence emission intensity of Eu3 is raised by inert fluorescent rare earth ions (Y3 , Gd3 and La3 ), but in Tb3 hetero-nuclear rare earth complexes the intensity of Tb3 ions are quenched by the inert fluorescent rare earth ions.     

Preparation,Photo and Electroluminescence Properties of Novel Rare Earth Aromatic Carboxylates

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Syntheses and Characterization of Binuclear Complexes Tb（1-x）Eux（TTA）3 Phen

Rare earth ternary complexes Tb1-xEux（TTA）3Phen（x=0,0.25,0.5,0.75,1.0）were synthesized and characterized by DTA-TG,XRD and infrared（IR）.The photophysical properties of these complexes were studied in detail using ultraviolet absorption spectra and fluorescent spectra.Ultraviolet absorption showed that the energy absorption of the complexes mostly came from ligands.Infrared spectra of Tb1-xEux（TTA）3Phen complexes were similar to the pure complexes.TG curves proved that the complexes were stable.Tb3＋ emission was almost quenched and the Eu3＋ emission was enhanced by codoping the complexes.The Tb3＋ ion acted as an energy transfer bridge that helped energy transfer from poly（N-vinylcar-bazole（PVK）to Eu3＋.In addition,their PL and EL properties were systematically studied.