Doping Concentration Of Tb3 Research Articles

X-Ray Excited Luminescence of Terbium Doped Sodium Aluminium Phosphate Glass

Luminescent materials which convert high energy photons to visible light are used for medical X-ray radiography. These materials contain luminescent centers with high efficiency, for example trivalent Tb ions in oxysulfide gadolinium ceramic. Generally, luminescent materials for X-ray radiography exhibit slower decay times than scintillators for photon-counting applications, however they also exhibit low afterglow. In this study, we researched about X-ray excited luminescence characteristics of sodium aluminium phosphate glass which is lower melting point than oxysulfide gadolinium ceramic. Tb doping concentrations of sodium aluminium phosphate samples were 0.3, 1.0, 3.0 and 10%, respectively. As a result of X-ray excited luminescence, emission peaks at wavelengths of around 480, 540, 580 and 620 nm were observed from each samples. Intensity of X-ray excited luminescence were increased with increasing of Tb doping concentration. Decay curves of samples were also evaluated by using X-ray induced afterglow characterization system [1] which was developed by our laboratory. Slow decay curves with time range of 20 milliseconds were successfully observed.[1] T. Yanagida, Y. Fujimoto, T. Ito, K. Uchiyama, K. Mori, "Development of X-ray induced afterglow characterization system" Appl. Phys. Exp., 7 062401 (2014).

Photoluminescence and long persistent luminescence properties of a novel green emitting phosphor Ca3TaAl3Si2O14:Tb3+

A Tb3+ doped Ca3TaAl3Si2O14 phosphor has been prepared successfully through a conventional solid-state reaction method. X-ray diffraction patterns indicate that the Tb3+ doping does not show obvious effect to the crystal structure of Ca3TaAl3Si2O14 (CTAS) host lattice. The luminescent properties were studied systematically by measuring photoluminescence spectra, decay curves, afterglow spectra and thermo-luminescence glow curves. The pure CTAS host with strong absorption in the range of 250–400 nm and could give a blue emission centered at about 493 nm. When Tb3+ ions were doped, the blue long afterglow (LAG) emission from Tb3+ was observed after stimulated by 254 nm ultraviolet lamp. The optimal doping concentration of Tb3+ for LAG performance was experimentally to be approximately 0.5 mol%. Based on the experimental results, a model was constructed and the relevant mechanism of afterglow was illustrated in detail.

Synthesis, Morphology Control and Luminescent Properties of Rare Earth Ion-Doped CaWO4 Microstructures.

Rare earth ions (Tb3+, Eu3+) doped CaWO4 microstructures were synthesized by a facile hydrothermal route without using any templates and characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence (PL) spectrum. The results indicate that the asprepared samples are well crystallized with scheelite structure of CaWO4, and the average diameter of the microstructures is 2~4 µm. The morphology of CaWO4:Eu3+ microstructures can be controllably changed from microspheres to microflowers through altering the doping concentration of Eul+ from 3% to 35%, and the microflowers are constructed by a number of CaWO4:Eu3+ nanoflakes. Under the excitation of UV light, the emission spectrum of CaWO4:Eu3+ is composed of the characteristics emission of Eu3+ 5D0-7FJ (J = 1, 2, 3, 4) transitions, and that of CaWO4:Tb3+ is composed of Tb3+ 5D4-7FJ (J= 6, 5, 4, 3) transitions. Both of the optimal doping concentrations of Tb3+ and Eu3+ in CaWO4 microstructures are about 5%.

Photoluminescence properties of Tb3+-doped stalk-like Al2O3

AbstractUniform Al2O3 : Tb3+ samples were successfully fabricated via a hydrothermal method and subsequent thermal decomposition of Tb3+ doped precursors. Scanning electron microscopy results showed Tb3+-doped Al2O3 was stalk-like with an average length about 1.5 μm. Photoluminescence spectra indicated that the 5D4 → 7F5 (545 nm) electric dipole transition was most intense upon excitation at 227 nm. It is shown that 1.5 mol.% doping concentration of Tb3+ ions in Al2O3 : Tb3+ is optimum. According to Dexter's theory, the critical distance between Tb3+ ions in Al2O3 for energy transfer was determined to be 14 Å.

Preparation and Luminescent Properties of the La<sup>3+</sup> Doped Tb<sup>3+</sup>-Hydroxyapatite

In this paper, a rare earth metal terbium ion as the central metal ion, a nanohydroxyapatite powder of the lanthanum doped terbium was synthesis by precipitation with hydroxyapatite as ligand. The sample was characterized by infrared spectrum, fluorescence spectrum and X ray diffraction instrument, and the thermal properties and fluorescence properties, structure of powderes were discussed. A nanohydroxyapatite powder of the lanthanum doped terbium achieves the maximum luminous intensity, when the La3+ doping concentration of Tb3+ was HAP 5% (La3+ and Tb3+ mole fraction ratio) devices. Rare earth powder of the lanthanum doped terbium hydroxyapatite has the stability chemical properties, the luminescence properties and good biological activity, the rare earth powder has good luminescent properties can be used in preparation of a good light emitting device. At the same time a nanohydroxyapatite powder of the lanthanum doped terbium has good antibacterial property, can be used as antibacterial materials.

Electrospinning preparation and photoluminescence properties of Y3Al5O12:Tb3+ nanostructures.

Novel nanostructures of Y3Al5O12:Tb(3+) (denoted as YAG:Tb(3+) for short) nanobelts and nanofibers were fabricated by calcination of the respective electrospun PVP/[Y(NO3)3 + Tb(NO3)3 + Al(NO3)3] composite nanobelts and nanofibers. YAG:Tb(3+) nanostructures are cubic in structure with a space group of Ia 3d. The thickness and width of the YAG:7%Tb(3+) nanobelts are respectively ca. 125 nm and 5.9 ± 0.3 m, and the diameter of YAG:7%Tb(3+) nanofibers is 166.0 ± 20 nm (95% confidence level). The YAG:Tb(3+) nanostructures emit predominantly at 544 nm from the energy levels transition of (5) D4 → (7) F5 of Tb(3+) ions under the excitation of 274-nm ultraviolet light. It was found that the optimum doping molar concentration of Tb(3+) ions for YAG:Tb(3+) nanostructures was 7%. Compared with YAG:7%Tb(3+) nanofibers, YAG:7%Tb(3+) nanobelts exhibit a stronger photoluminescence (PL) intensity under the same doping concentration. Commission International de l'Eclairage (CIE) analysis demonstrates that the emitting colors of YAG:Tb(3+) nanostructures are located in the green region and color-tuned luminescence can be obtained by changing the doping concentration of Tb(3+) and morphologies of the nanostructures, which could be applied in the field of optical telecommunication and optoelectronic devices. The possible formation mechanisms of YAG:Tb(3+) nanobelts and nanofibers are also proposed.

Synthesis and luminescence of high-brightness Gd2O2SO4:Tb3+ nanopieces and the enhanced luminescence by alkali metal ions co-doping

Gd2O2SO4:Tb3+ nanopieces were synthesized by a combined approach of electrospinning and calcination at 1000°C in mixed gas of sulfur dioxide and air. The nanopieces excited by a 230nm light showed excellent green luminescence with the strongest emission peak at 545nm due to the 5D4→7F5 transition of Tb3+. Interestingly, the intensity of emission peak at 545nm of Gd2O2SO4:Tb3+ nanopieces exhibited about two times stronger than that of the bulk Gd2O2SO4:Tb3+ at the same doping concentrations of Tb3+. Besides, the effects of alkali metal ions doping on the luminescence of the nanopieces have been examined. The emission intensities were further enhanced by alkali metal ions doping, especially for Gd2O2SO4:Tb3+/Li+. The optimal doping concentration of Li+ was 7%.

Fabrication and luminescence of YF3:Tb3+ hollow nanofibers

YF3:Tb3+ hollow nanofibers were successfully fabricated via fluorination of the relevant Y2O3:Tb3+ hollow nanofibers which were obtained by calcining the electrospun PVP/[Y(NO3)3 + Tb(NO3)3] composite nanofibers. The morphology and properties of the products were investigated in detail by X-ray diffraction, scanning electron microscope, transmission electron microscope, and fluorescence spectrometer. YF3:Tb3+ hollow nanofibers were pure orthorhombic phase with space group Pnma and were hollow-centered structure with the mean diameter of 148 ± 23 nm. Fluorescence emission peaks of Tb3+ in the YF3:Tb3+ hollow nanofibers were observed and assigned to the energy levels transitions of 5D4 → 7FJ (J = 6, 5, 4, 3) (490, 543, 588, and 620 nm) of Tb3+ ions, and the 5D4 → 7F5 hypersensitive transition at 543 nm was the dominant emission peak. Moreover, the emitting colors of YF3:Tb3+ hollow nanofibers were located in the green region in CIE chromaticity coordinates diagram. The luminescent intensity of YF3:Tb3+ hollow nanofibers was increased remarkably with the increasing doping concentration of Tb3+ ions and reached a maximum at 7 mol% of Tb3+. The possible formation mechanism of YF3:Tb3+ hollow nanofibers was also discussed. This preparation technique could be applied to prepare other rare earth fluoride hollow nanofibers.

ZnAl2O4∶Tb3+荧光粉的合成、结构及其光学性能研究

通过溶胶-凝胶法制备出不同Tb3+掺杂浓度和不同二次煅烧温度下的ZnAl2O4∶Tb3+荧光粉,并利用X射线衍射(XRD)和荧光光谱等对样品进行了表征。由XRD结果可知,当Tb3+掺杂的摩尔分数不大于9%,二次煅烧温度在600℃以上时,所得粉体为结晶性良好的尖晶石相。在紫外光激发下,ZnAl2O4∶Tb3+荧光粉的发射光谱由位于488 nm(5D4→7F6)、542 nm(5D4→7F5)、587 nm(5D4→7F4)和621.5 nm(5D4→7F3)的4个发射峰组成。研究发现,Tb3+的掺杂浓度和二次煅烧温度对样品发光强度有着重要影响,当Tb3+的摩尔分数为5%,二次煅烧温度为900℃时,ZnAl2O4∶Tb3+荧光粉的发光最强,继续增加Tb3+掺杂浓度或提高煅烧温度,分别会出现浓度猝灭和温度猝灭现象。

Electrospinning preparation of LaOBr:Tb3+ nanostructures and their photoluminescence properties

Tb3+-doped LaOBr nanostructures including nanofibers, nanobelts, and hollow nanofibers were synthesized for the first time via calcinating the electrospun polyvinyl pyrrolidone/[La(NO3)3 + Tb(NO3)3 + NH4Br] composites. X-ray diffraction analysis revealed that LaOBr:Tb3+ nanostructures are tetragonal in structure with space group of P4/nmm. The morphologies and sizes of LaOBr:Tb3+ nanostructures were investigated using scanning electron microscope and transmission electron microscope. Under the excitation of 254-nm ultraviolet light, LaOBr:Tb3+ nanostructures exhibit the green emissions of predominant peak at 543 nm, which is ascribed to 5D4 → 7F5 transition of Tb3+ ions. It is found that the optimum doping concentration of Tb3+ ions in the LaOBr:Tb3+ nanofibers is 3 %. Interestingly, we found that the luminescence intensity of hollow nanofibers is obviously greater than that of nanofibers and nanobelts for LaOBr:Tb3+ under the same measuring conditions. Moreover, the luminescence of LaOBr:Tb3+ nanostructures are located in the green region in Commission Internationale de L’Eclairage chromaticity coordinates diagram. The formation mechanisms of LaOBr:Tb3+ nanofibers, nanobelts, and hollow nanofibers were also proposed. LaOBr:Tb3+ nanostructures are promising nanomaterials for applications in the fields of light display systems and optoelectronic devices.

Luminescence properties and efficient energy transfer in Ce3+ and Tb3+ co-doped Mg2La3[SiO4]2[PO4]O phosphor

A series of Ce 3+ , Tb 3+ singly doped and Ce 3+ / Tb 3+ -co-doped Mg 2 La 3 [SiO 4 ] 2 [PO 4 ]O phosphors with the apatite-like structure were prepared by conventional solid-state reaction. The X-ray diffraction (XRD), photoluminescence excitation and emission spectra, luminescence decay curves and lifetimes were applied to characterize the samples. The efficient excitation energy transfer from Ce 3+ to Tb 3+ was verified by the excitation and emission spectra together with the luminescence decay curves. The Ce 3+ /Tb 3+ co-doped phosphor shows an intense broad excitation band between 300 and 430 nm, which matches near-UV chip (350–420 nm). Under the excitation of near UV light, the Ce 3+ /Tb 3+ co-doped sample exhibits two distinct luminescence bands: a blue one centered at about 415 nm originating from Ce 3+ ions and a green-emitting at 543 nm from the 5 D 4 → 7 F 5 transition of Tb 3+ ions. The emission can be tuned from the blue to the green color by changing the doping concentration of Tb 3+ . The energy transfer from Ce 3+ to Tb 3+ has been demonstrated to be the dipole–quadrupole mechanism, and the critical distance is calculated to be 16.04 Å.

Highly Thermostable One-Dimensional Lanthanide(III) Coordination Polymers Constructed from Benzimidazole-5,6-dicarboxylic Acid and 1,10-Phenanthroline: Synthesis, Structure, and Tunable White-Light Emission

Three novel isostructural lanthanide(III) coordination polymers (LnCPs), {[Ln3(bidc)4(phen)2(NO3)]·2H2O}n (Ln = Gd (1), Eu (2), Tb (3); H2bidc = benzimidazole-5,6-dicarboxylic acid, and phen = 1,10-phenanthroline), were synthesized via hydrothermal reaction and characterized. The complexes crystallize in the chiral space group P212121. They possess 1D structures based on lanthanide trinuclear clusters containing Ln(1)O9, Ln(2)O6N2, and Ln(3)O6N2 polyhedra by bidc linkers, and phen and nitrate act as terminal ligands. The bidc and phen ligands provide efficient energy transfer for the sensitization of Eu(III) and Tb(III) complexes. The complexes 2 and 3 emit red and green light, respectively. Lifetimes and quantum yields of luminescence are 0.86 ms and 13.20% for 2 and 0.32 ms and 2.08% for 3. Tuning of white-light emission by adjusting the doping concentration of Eu(III) and Tb(III) ions in the Gd(III) complex was achieved.

Sol-Gel Combustion Synthesis and Properties of Nanocrystalline TbxY1-x Al<sub>3</sub>(BO<sub>3</sub>)4（0≤x≤0.2）Phosphors

Single phases of TbxY1-x Al3(BO3)4（0≤x≤0.2）phosphors were synthesized by a sol-gel combustion method with citric acid as fuel and complexing agent. Our method involves only exothermic decomposition of an aqueous citrate–nitrate gel and the gel yielded nanocrystalline TbxY1-x Al3(BO3)4 phosphors at 1000°C, without any formation of intermediate phase. The optimal doping concentration of Tb3+ ions in the serials was found to be approximately 12mol%. The decomposition of the gel was investigated by TG–DTA. The product has been further characterized by X-ray powder diffractometry (XRD) and fluorescent divide spectroscopy (FDS).

Synthesis and Luminescence Properties of Tb<sup>3+</sup>-Doped Hydroxyapatites

In this paper, the terbium -doped nano-HA powders with strong fluorescence was prepared by hydrothermal synthesis and its crystal structure，morphology and fluorescent properties are characterized by XRD, TEM, XPS, ICP and PL spectroscopy. Results showed that with the doping concentration of Tb3+increasing, the aspect ratio of Tb3+-doped HA particles decreased, while the fluorescence intensity excited by ultraviolet ray at 272 nm is significantly enhanced. With pH values increased from 6.5 to 10.0, the aspect ratio of Tb3+-doped HA decreased greatly, and the morphology of nano-Tb:HA particles changes from rod particles to equiaxed particles and the actual doping content and the fluorescence intensity tends to increase correspondingly, which can be explained that under alkaline solution, Tb3+was more easier entering the HA crystal, and the Tb3+would substitute the Ca2+ in both hydroxyapatite Ca(Ⅰ) and Ca(Ⅱ) site, which may block the active growth sites of the seed crystals and resulted in the growth rate and the ratio of length to radius decreasing.

Photoluminescence of TiO 2 films co-doped with Tb 3+/ Gd 3+and energy transfer from TiO 2/Gd 3+ to Tb 3+ ions

Nanometer TiO 2 thin films doped with different concentration of Tb were prepared by sol–gel method and characterized by X-ray diffraction (XRD), thermogravimetry–differential thermal analysis (TG-DTA), transmission electron microscopy (TEM) and photoluminescence (PL) spectroscopy. XRD results show preferentially oriented (101) anatase films. TEM image indicates that the TiO 2 films consist of TiO 2 grains with diameter about 15 nm. Under room temperature, strong visible luminescence of Tb 3+ ions due to intra-4f shell transitions are obtained and the PL intensity is found to have a well matching relation with the doping concentration of Tb 3+ ions. Concentration quenching of PL occurs when Tb 3+ concentration exceeds a certain value (9.2 mol%). Furthermore, the luminescence intensity is improved obviously after co-doping with Gd 3+ ions because of the sensitization effects of Gd 3+ ions to Tb 3+ ions in TiO 2 system. The energy transfer mechanism from TiO 2 and Gd 3+ ions to Tb 3+ ions was proposed.

Photoluminescence properties of β-Ga2O3:Tb3+ nanofibers prepared by electrospinning

One-dimensional Tb3+-doped beta-Ga2O3 nanofibers were prepared by a simple and cost-effective electrospinning process. Field emission scanning electron microscopy (FE-SEM). X-ray diffraction (XRD), Raman technique, and photoluminescence (PL) were used to characterize the electrospun nanofibers. FE-SEM results indicated that the diameters all of the nanofibers ranged from 100 to 300 nm, and the lengths of nanofibers reached up to several millimeters. The XRD and Raman results showed that the Ga2O3 phase belongs to the monoclinic phase. Under ultraviolet excitation, the beta-Ga2O3:Tb3+ samples showed green emission with the strongest peak at 550 nm, corresponding to D-5(4) -> F-7(5) transition of Tb3+ ions. The luminescence intensity had been further studied as a function of the doping concentration of Tb3+ in the beta-Ga2O3 samples. (C) 2011 Elsevier B.V. All rights reserved.

Facile synthesis and luminescence properties of uniform and monodisperse KY 3F 10:Ln 3+ (Ln=Eu, Ce, Tb) nanospheres

Highly uniform and monodisperse KY 3F 10:Ln 3+ (Ln=Eu, Ce, Tb) nanospheres, with an average diameter of 300 nm, have been successfully prepared through a simple template-free and surfactant-free stirring method under ambient conditions. X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence (PL) spectra were used to characterize the samples. The SEM images illustrate that these spheres were actually composed of randomly aggregated nanoparticles. The doped rare earth ions show their characteristic emission in the KY 3F 10 samples, i.e., Eu 3+ 5D 0– 7F J ( J=1, 2, 3, 4), Tb 3+ 5D 4– 7F J ( J=6, 5, 4, 3, 2) and Ce 3+ 5d–4f transition emissions, respectively. An energy transfer phenomenon from Ce 3+ to Tb 3+ has been observed in KY 3F 10 nanospheres, and the energy transfer efficiency depends on the doping concentration of Tb 3+ if the concentration of Ce 3+ is fixed.

The Quantum Cutting of Tb3+ in Ca6Ln2Na2(PO4)6F2 (Ln = Gd, La) under VUV−UV Excitation: with and without Gd3+

The VUV-vis spectroscopic properties of Tb(3+) activated fluoro-apatite phosphors Ca(6)Ln(2-x)Tb(x)Na(2)(PO(4))(6)F(2) (Ln = Gd, La) were studied. The results show that phosphors Ca(6)Gd(2-x)Tb(x)Na(2)(PO(4))(6)F(2) with Gd(3+) ions as sensitizers have intense absorption in the VUV range. The emission color of both phosphors can be tuned from blue to green by changing the doping concentration of Tb(3+) under 172 nm excitation. The visible quantum cutting (QC) via cross relaxation between Tb(3+) ions was observed in cases with and without Gd(3+). Though QC can be realized in phosphors Ca(6)La(2-x)Tb(x)Na(2)(PO(4))(6)F(2), we found that Gd(3+)-containg phosphors have a higher QC efficiency, confirming that the Gd(3+) ion indeed plays an important role during the quantum cutting process. In addition, the energy transfer process from Gd(3+) to Tb(3+) as well as (5)D(3)-(5)D(4) cross relaxation was investigated and discussed in terms of luminescence spectra and decay curves.

Modeling of Tunable Luminescence in Multiple Rare Earth Co-Doped Glasses

As luminescence from co-doping systems is highly sensitive to the glass host and concentration of active ions due to complicated electronic transitions within respective active ions and complex energy transfer between them, it is desirable to develop a theoretical model to design and optimize the co-doping system before the fabrication and measurement of the sample. In this paper, we present a numerical approach to model the generation of tunable visible luminescence in multiple rare earth co-doped glasses. According to our research, a glass system with a special combination of Tb3+, Sm3+ and Dy3+ ions can emit tunable luminescence. When glasses co-doped with proper doping concentration of Tb3+ /Sm3+ /Dy3+ ions are excited by different wavelength in the range of 370-410 nm, the luminescent color can be tuned from yellowish white to orange-red. Our work suggests that the tunable luminescence from multiple rare earth co-doped glasses could have further application in colorful light emitting and other display devices.

Luminescence properties of ZnGa2O4 and ZnAl2O4 spinels doped with Eu3+ and Tb3+ ions

AbstractSpinel‐type ZnGa2O4 and ZnAl2O4 powders doped with Eu3+ and Tb3+ ions, including dual doping, have been prepared by solid phase reactions and by deposition from chemical solutions. XRD analysis demonstrates the high quality of spinel grains constituting the powder. The luminescence shows that the rare earth ions are incorporated in the defect regions at the grain boundaries. The emission spectra of the samples with europium are characterized by an intense emission in red region due to the 5D0 → 7F1,2 transitions of Eu3+ ions, whereas in the case of terbium the highest intensity corresponds to the green emission due to the 5D4 → 7F5 transitions of Tb3+ ions. The possibility to change the color of the emission from green to red by the variation of Tb and Eu doping concentration is demonstrated. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)