• Title/Summary/Keyword: Terbium

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Photoluminescence properties of eight coordinated terbium(III) complexes (8배위 터븀 (III) 착화합물의 합성과 Photoluminescence 특성)

  • Yun, Myung-Hee;Kim, Yeon-Hee;Choi, Won-Jong;Chang, Choo-Hwan;Choi, Seong-Ho
    • Analytical Science and Technology
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    • v.24 no.6
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    • pp.451-459
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    • 2011
  • Eight coordinated terbium(III) complexes, tris (2-pyrazinecarboxylato)(phenanthroline) terbium(III) [$Tb(pzc)_3$(phen)], tris (5-methyl-2-pyrazinecarboxylato) (phenanthroline) terbium(III) [$Tb(mpzc)_3$(phen)] and tris(2-picolinato) (phenanthroline) terbium(III) [$Tb(pic)_3$(phen)], have been synthesized and characterized by Fourier transform infrared (FT-IR), UV-Visible and X-ray photoelectron spectroscopy. Photoluminescence (PL) spectroscopy shows that these complexes emitted strong green luminescence. When powder samples of the $Tb^{3+}$ complexes are examined using time-resolved spectroscopic analysis, the luminescence lifetimes are found to be 0.87 ms and 1.0 ms, respectively. Thermogravimetric analysis reveals the terbium complexes to have good thermal stability up to $333-379^{\circ}C$. Cyclic voltammetry shows that HOMO-LUMO energy gap of the $Tb^{3+}$ complexes ranges from 4.26~4.41 eV. These values are similar to those obtained from the UV-visible spectra. Overall, the synthesized $Tb^{3+}$ complexes may be useful advanced materials for green light emitting devices.

Determination of Tb(III) in aqueous solution by fluorescence spectrometry (형광분광법에 의한 수용액 중의 Tb(III) 정량)

  • Lee, Sang Hak;Bae, Zun Ung;Chung, Hae Young;Choi, Sang Seob
    • Analytical Science and Technology
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    • v.10 no.4
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    • pp.274-281
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    • 1997
  • Methods to determine terbium(III) ion in aqueous solution by measuring the enhanced fluorescence intensity of terbium(III)-terephthalic acid(TPA) complex ion have been studied. The optimum analytical conditions for pH, excitation wavelength and concentration of TPA were found to be 6.0, 260nm and $4.0{\times}10^{-4}M$, respectively. The fluorescence intensity of the terbium(III) complex ion was further increased with addition of trioctylphosphine oxide (TOPO). In this case Triton X-100 was used to dissolve TOPO in aqueous solution. When TOPO was used, the optimum analytical conditions for pH, excitation wavelength, and concentrations of TPA, TOPO and Triton X-100 were found to be 4.5, 285nm. $4.0{\times}10^{-4}M$, $5.0{\times}10^{-5}M$, and 0.05%, respectively. Under the optimum experimental conditions, calibration curve for Tb(III) was linear over the range from $4.0{\times}10^{-8}M$ to $4.0{\times}10^{-5}M$ and the detection limit was $4.0{\times}10^{-8}M$. When TOPO was used, the concentration range of linear response, and the detection limit were $4.0{\times}10^{-9}M$ to $2.0{\times}10^{-6}M$, and $4.0{\times}10^{-9}M$, respectively. Effects of interferences from various cations for the determination of terbium(III) ion were also investigated.

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Photoluminescent and Electroluminescent Characteristics of Thin Films of Terbium Complex with Various Ligand Prepared by Vacuum Evaporation Method (진공 증착법에 의한 다양한 Terbium Complexes 박막의 광학적 및 전기적 특성 연구)

  • 표상우;이명호;이한성;김영관;김정수
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1998.11a
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    • pp.315-318
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    • 1998
  • Organic light-emitting diodes(OLEDs) or electroluminescent devices have attracted much attention because of their possible application as large-area light-emitting displays. Their structure was based on employing a multilayer device structure containing an emitting layer and a carrier transporting layer of suitable organic materials. In this study, several Tb complexes such as Tb(ACAC)$_3$(Phen), Tb(ACAC)$_3$(Phen-Cl) and Tb(TPB)$_3$(Phen) were synthesized and the photoluminescence(PL) and electroluminescence (EL) characteristics of their thin films were investigated by fabricating the devices having a structure of anode/HTL/terbium-oomplex/ETL/cathode, where TPD was used as an hole transporting and Alq$_3$ and TAZ-Si were used as an electron transporting materials. It was found that the photoluminescence(PL) and electroluminescence(EL) characteristics of these terbium complexes were dependent upon the ligands coordinated to terbium metal. Details on the explanation of electrical transport phenomena of the structure with I-V characteristics of the OLEDs using the trapped-charge-limited current(TCLC) model will be discussed.

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Effect of Metal Chloride Coloring Liquids on Color and Strength Changes of Tetragonal Zirconia Polycrystals (금속염화물 착색제 침투가 정방정 지르코니아 다결정체의 색조와 강도 변화에 미치는 영향)

  • Oh, Jong-Jin;Noh, Hyeong-Rok
    • Journal of dental hygiene science
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    • v.15 no.5
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    • pp.577-584
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    • 2015
  • The purpose of this study was to evaluate the effect of metal chloride infiltration treatment on color and strength changes of the yttria-stabilized tetragonal zirconia polycrystals (Y-TZP). Fifty disc specimens were prepared with a Y-TZP powder (ZPEX; Tosoh, Japan). Thirty different metal chloride solutions containing 0.03~0.08 wt% chromium and 0.03~0.07 wt% terbium ions were prepared. Presintered Y-TZP specimens were soaked in metal chloride coloring liquids for 3 minutes and sintered in air at $1,450^{\circ}C$ for 2 hours. The color of the specimens was measured with spectrophotometer and color difference (${\Delta}E^*$) was obtained based on the CIE $L^*$, $a^*$, $b^*$ color coordinate values. To evaluate the effect of metal chloride infiltration strength changes, the biaxial flexural test was performed at crosshead speed 0.5 mm/min. Colors of the sintered Y-TZP showed the colors of Vita shade guide A1, A2 and A3 with the infiltration of chromium and terbium chloride solutions. Density of the sintered Y-TZP increased by the infiltration of chromium and terbium chloride solutions. Bi-axial flexural strength of the sintered Y-TZP did not show statistically significant differences by the infiltration of chromium and terbium chloride solutions (p>0.05). Chromium and terbium chloride did not affect the crystal phase of zirconia, and all specimens showed tetragonal phase. Accordingly, this study suggests that chromium and terbium chlorides can make colored zirconia while adding in a liquid form. The color of colored zirconia differ from that of vita shade guide but it can use all ceramic restoration as substructure in dental clinic.

Separation of High Purity Terbium Using Extraction Chromatography (추출 크로마토그래피를 이용한 고순도 테르븀의 분리)

  • Lee, Kwang-Pill;Park, Myoung-Jin;Park, Keung-Shik;Lee, Hueng-Lark;Piao, Zhexiu
    • Analytical Science and Technology
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    • v.12 no.5
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    • pp.370-374
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    • 1999
  • Extraction chromatography was used to scarch optimum separation conditions of terbium. Stationary phase was 2-ethylhexyl-2-ethylhexyl phosphonic acid(HEH[EHP])levextrel (-100~+150 mesh), column size was ${\Phi}20{\times}530mm$ and kept constantly temperature at $50^{\circ}C$, adsorption flow rate of $0.2mL/cm^2{\cdot}min$, elution flow rate of $1.0mL/cm^2{\cdot}min$, column diameter to packing height of 1:15. But to search optimum separation conditions of terbium, it changed the eluent acidity, the loading weight of sample. the composition of sample. In conclusion, acidity was 0.6 N HCl, loading weight of sample was about 5% and composition of sample was $Gd_2O_3(20%)+Tb_4O_7(60%)+Dy_2O_3(20%)$. Moreover purity of separated terbium by ICP-AES analysis was 99.98% in yield of 99.99%.

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3-Dimensional Terbium Coordination Polymers: [Tb4(NDC)6(H2O)5]·2H2O and [Tb2(BPDC)3(H2O)3]·H2O(NDC = 2,6-Naphthalenedicarboxylate; BPDC = 2,2'-Bipyridine-4,4'-dicarboxylate)

  • Min, Dong-Won;Lee, Soon-W.
    • Bulletin of the Korean Chemical Society
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    • v.23 no.7
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    • pp.948-952
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    • 2002
  • Three-dimensional terbium coordination polymers with the formulas of [Tb4(NDC)6(H2O)5]${\cdot}$2H2O (1) and [Tb2(BPDC)3(H2O)3]${\cdot}$H2O (2) (NDC = 2,6-naphthalenedicarboxylate; BPDC = 2,2'-bipyridine-4,4'-dicarboxy-late) were prepared by hydrothermal reactions. Both compounds were structurally characterized by X-ray diffraction. Compound 1 has a polymeric structure that contains four distinct Tb metals. Three Tb metals have a square-antiprismatic structure, and the remaining one has a 9-coordinate, triply capped trigonal-prismatic structure. Compound 2 is also a polymer with two distinct Tb metals, both of which have a square-antiprismatic structure. The pyridine nitrogen atoms of the BPDC 2- ligand do not coordinate to the metal centers in compound 2.

Preparation of Terbium Complex Films by Vacuum Evaporation Method and Their Characterization (진공 증착법에 의한 Terbium Complex 박막의 제작 및 특성 연구)

  • Pyo, Sang-Woo;Kim, Young-Kwan;Son, Byoung-Chung
    • Journal of the Korean Applied Science and Technology
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    • v.15 no.3
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    • pp.85-90
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    • 1998
  • In this study, organic electroluminescent devices(OELD) with a structure of a glass $substrate/ITO/TPD/Tb(ACAC)_3(Phen-Cl)/Alq_3/Al$ was fabricated by vacuum evaporation method, where Tb complex was known to have green light emitting property. Electroluminescent(EL) and I-V characteristics of this structure were investigated. This triple-layer structure shows the green EL spectrum at the wavelwngth of 546nm, which is almost the same as the PL spectrum of $Pb(ACAC)_3(Phen_Cl)$. It was found in current-voltage(I-V) characteristics of the devices that the operating voltage was about 12V.

Luminescence and Crystal-Field Analysis of Europium and Terbium Complexes with Oxydiacetate and 1,10-Phenanthroline

  • Kang, Jun-Gill;Kim, Tack-Jin
    • Bulletin of the Korean Chemical Society
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    • v.26 no.7
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    • pp.1057-1064
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    • 2005
  • Photoluminescence (PL) spectra of Eu(III) and Tb(III) complexes with mixed oxydiacetate (ODA) and 1,10-phenanthroline (phen) ligands and with homoleptic ODA reveal characteristic line-splitting at 10 K, depending on the site-symmetry of the lanthanide ion in the complex. The energy-level schemes of the $^7F_J$ states and the emitting levels for Eu(III) and Tb(III) ions have been proposed by simulating the line splitting in the framework of crystal-field Hamiltonian. The sets of refined crystal-field parameters for the experimentally determined sitesymmetry satisfactorily reproduce the experimental energy-level schemes. In addition, the PL quantum yield and the decay time were determined at room temperature. The PL quantum yields of [$Eu(ODA){\cdot}(phen){\cdot}4H_2O]^+$ and [Tb$(ODA){\cdot}(phen){\cdot}4H_2O]^+$ in the crystalline state (Q = 17.7 and Q = 56.6%, respectively) are much greater than those of [Eu($ODA)_3]^{3-}and\;[Tb(ODA)_3]^{3-}$(Q = 1.1 and Q = 1.3, respectively), due to the energy transfer from phen to the lanthanide ion. In the aqueous state, the relaxation of the phen moiety due to the solvent results in the reduction of the quantum yield and the shortening of the lifetime.