• Title/Summary/Keyword: LaNiO3

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Structural and electrochemical characterization of K2NiF4 type layered perovskite as cathode for SOFCs (K2NiF4 type 층상 페롭스카이트 구조 La(Ca)2Ni(Cu)O4-δ의 SOFC 양극 특성 및 결정구조 평가)

  • Myung, Jae-ha;Hong, Youn-Woo;Lee, Mi Jai;Jeon, Dae-Woo;Lee, Young-Jin;Hwang, Jonghee;Shin, Tae Ho;Paik, Jong Hoo
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.25 no.3
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    • pp.116-120
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    • 2015
  • $La_2NiO_{4+{\delta}}$ based oxides, a mixed electronic-ionic conductors (MIECs) with $K_2NiF_4$ type structure, have been considerably investigated in recent decades as electrode materials for advanced solid oxide fuel cells (SOFCs) due to their high electrical conductivity, and oxidation reduction reaction (ORR). In this study, structure properties of $La(Ca)_2Ni(Cu)O_{4+{\delta}}$ were studied as a potential cathode for intermediate temperature SOFCs (IT-SOFCs).

Crystal Molecular Orbital Calculation of the Lanthanum Nickel Oxide by Means of the Micro-Soft Fortran (마이크로-소프트 포트란을 이용한 복합 산화물 결정의 분자 궤도함수 계산)

  • Koo, Hyun-Joo;Lee, Kwang-Soon;Ahn, Woon-Sun
    • Journal of the Korean Chemical Society
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    • v.39 no.9
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    • pp.685-691
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    • 1995
  • EHMACC and EHPC programs written in VAX version to calculate the tight-binding extended Huckel method is converted into the micro-soft fortran available to PC. The band calculation of LaNiO3 unit cell and extended ($2{\times}2{\times}1$) cell with perovskite structure is made by the PC/386 and PC/486. The calculation is also made for the DOS and the COOP. It is supposed that the electronic property of $LaNiO_3$ is semiconductor along to the ${\Gamma}{\rightarrow}H,\;H{\rightarrow}N,\;and\;N{\rightarrow}{\Gamma}(2D)$ direction with band gap about 0u.35 eV, while metal property in ${\Gamma}{\rightarrow}P\;and\;P{\rightarrow}N(3D)$ direction. The oxygen atom property in $LaNiO_3$ is more effectively affected by oxygen atom position than defect of nickel atom.

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A Study on the Oxidation of Carbon Monoxide for Exhaust of Car Engine by the $LaSrNiCoO_3$ Low Noble Metal Catalyst (저귀금속 $LaSrNiCoO_3$ 촉매에 의한 자동차 배기중의 일산화탄소의 산화반응에 관한 연구)

  • 이근배;이석희
    • Journal of Korean Society for Atmospheric Environment
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    • v.6 no.1
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    • pp.57-72
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    • 1990
  • The oxidation of carbon monoxide on a catalyst, $LaSrNiCoO_3$ was investigatigated with a plug flow system. Kinetic quantities such as reaction-rate, reaction order and Arhenius-parameters at various reactor temperature from 200$^\circ$C to 300$^\circ$C were determined. Also, the optimum condition for the oxidation of carbon monoxide with this catalyst was determined and are as follows. Partial pressure of oxigen ; 428mmHg Partial pressure of carbon monoxide ; 332mmHg Mixed moral ratio of oxigen and Carbon monoxide ; 1.3 : 1 Total gas flow ; 224ml/min Reaction temperature ; 340$^\circ$C The reaction kinetic equation at the optimum condition, temperature range from 200$^\circ$C to 340$^\circ$C, are as follow. $$ $v = Ae^{6.5Kcal/RT} [CO]^{0.93 \sim 0.98} [O_2]^{0.42 \sim 0.50}$ $$ In addition to this, numerical calculation were performed to evaluate the mass and heat transfer effect on this system.

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The Study on the Catalytic Performance and Characterization of La0.9Sr0.1Cr0.7B0.3O3±δ (B=Mn, Ni, Fe, Ru) for High Temperature Water-gas Shift Reaction with Simuated Coal-derived Syngas (모사된 석탄가스화 합성가스를 이용한 La0.9Sr0.1Cr0.7B0.3O3±δ (B=Mn, Ni, Fe, Ru)의 수성가스전이반응 활성 및 특성에 관한 연구)

  • Lee, Seul-Gi;Kwak, Jaehoom;Sohn, Jung Min
    • Transactions of the Korean hydrogen and new energy society
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    • v.24 no.6
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    • pp.543-549
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    • 2013
  • In this study, $La_{0.9}Sr_{0.1}Cr_{0.7}M_{0.3}O_{3{\pm}{\delta}}$ (M=Mn, Ru, Fe, Ni) were prepared by sol-gel method and water gas shift reaction with simulated coal-derived syngas between $400{\sim}650^{\circ}C$ was conducted to evaluate the catalytic activity of prepared catalysts. Physico-chemical properties were characterized by XRD, BET, SEM-EDS and TPR. The formation of perovskite crystallite, $LaCrO_3$ was confirmed and the highest surface area was measured with $La_{0.9}Sr_{0.1}Cr_{0.7}Mn_{0.3}O_{3{\pm}{\delta}}$. Equilibrium conversion of CO above $550^{\circ}C$ was achieved except $La_{0.9}Sr_{0.1}Cr_{0.7}Fe_{0.3}O_{3{\pm}{\delta}}$. and methanation reaction was carried out as side reaction of water gas shift reaction with $La_{0.9}Sr_{0.1}Cr_{0.7}Ni_{0.3}O_{3{\pm}{\delta}}$ and $La_{0.9}Sr_{0.1}Cr_{0.7}Ru_{0.3}O_{3{\pm}{\delta}}$. Conclusively, $La_{0.9}Sr_{0.1}Cr_{0.7}M_n{0.3}O_{3{\pm}{\delta}}$ was the most suitable catalyst of water gas shift reaction above $500^{\circ}C$ for CO conversion and hydrogen production.

temperature synthesis and ferroelectric properties of (117)-oriented $Bi_{3.25}La_{0.75}Ti_3O_{12}$ thin films on $LaNiO_3$ electrodes

  • Kim, Kyoung-Tae;Kim, Chang-Il
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.11a
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    • pp.264-267
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    • 2004
  • [ $Bi_{3.25}La_{0.75}Ti_3O_{12}$ ] (BLT) thin films were prepared by using metal organic decomposition method onto the $LaNiO_3$ (LNO) bottom electrode. Both the structure and morphology of the films were analyzed by x-ray diffraction (XRD) and atomic force microscope (AFM). Even at low temperatures ranging from 450 to $650^{\circ}C$, the BLT thinfilms were successfully deposited on LNO bottom electrode and exhibited (117) orientation. The BLT thin films annealed as low as $600^{\circ}C$ showed excellent ferroelectricity, higher remanent polarization and no significant degradation of switching charge at least up to $5{\times}10^9$ switching cycles at a frequency of 100 kHz and 5 V. For the annealing temperature of $600^{\circ}C$, the remanent polarization Pr and coercive field were $23.5\;C/cm^2$ and 120 kV/cm, respectively.

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The Effect of Surface Modification with La-M-O (M = Ni, Li) on Electrochemical Performances of Li[Ni0.8Co0.15Al0.05]O2 Cathode

  • Ryu, Jea-Hyeok;Kim, Seuk-Buom;Park, Yong-Joon
    • Bulletin of the Korean Chemical Society
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    • v.30 no.3
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    • pp.657-660
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    • 2009
  • The surface of $Li[Ni_{0.8}Co_{0.15}Al_{0.05}]O_2$ cathode particle was modified by lanthanum based oxide to improve electrochemical property and thermal stability. The XRD pattern of surface layer was indexed with that of $La_4NiLiO_8$. The discharge capacity of modified electrode was higher than that of pristine sample, specially at fast charge-discharge rate and high cut-off voltage. In the DSC profile of the charged sample, the generation of heat by exothermic reaction was decreased by surface modification. Such enhancement may by attributed to the presence of stable lanthanum based oxide, which effectively suppressd the reaction between electrode and electrolyte on the surface of $Li[Ni_{0.8}Co_{0.15}Al_{0.05}]O_2$ electrode.

AC & DC Electrical Characterization of PTC $BaTiO_3$ and Electrodes (PTC $BaTiO_3$ 및 전극의 직류 및 교류 특성)

  • 전표용;최경만
    • Journal of the Korean Ceramic Society
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    • v.28 no.2
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    • pp.101-108
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    • 1991
  • 0.2 mo1% La doped BaTiO3 samples were prepared by a wet chemical process (Pechini process) and electrical conductivity were measured from annealing temperatures(800-110$0^{\circ}C$) to room temperature continuously. 2 probe I-V characteristics showed that Pt electrodes were non-ohmic below about 80$0^{\circ}C$ for Ladoped sample. I-V curves showed varistor behavior and breakdown voltages showed PTC-like behavior. AC complex impedance of 0.2 La and 0.05 Mn mo1% doped BaTiO3 samples with three different electrodes (electroless Ni, Pt, Ag electrodes) were measured with temperature variation. Complex impedance plots showed that the samples with electroless Ni electrodes have negligible electrode resistance. Samples with Ag or Pt paste electrodes showed large electrode resistance. PTC effect, which is defined as the ratio of maximum resistance to minimum resistance, was found to be less than 10 for 0.2 mo1% La doped dense sample however greater than 105 with codoping of 0.05 mo1% Mn and 0.2 mol% La.

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The Effect of NiO and $MnO_2$ Addition on the Dielectric Piezoelectric and Polarization-Reversal Properties of PLZT (NiO와 $MnO_2$ 의 첨가가 PLZT의 유전특성과 압전특성 및 분극반전특성에 미치는 효과)

  • 조경익;주웅길;고경신
    • Journal of the Korean Ceramic Society
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    • v.20 no.4
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    • pp.315-323
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    • 1983
  • Effect of NiO and $MnO_2$ addtivies on the dielectric piezoelectrics and polarization-reversal properties of $(Pb_{0.936} La_{0.064})$$(Zr_{0.60}Ti_{0.40})O_3$ ceramics have been investigated. The specimens were prepared by the mixed oxide techni-que and atmosphere sintering method. The room temperature X-ray diffraction studies show that perfect perovskite solution with tetragonal structure was obtained from PLZT and its additives. The dielectric constant and dissipation factor decreased with the addition of both NiO and $MnO_2$ The Curie of Curie temperature was not observed but they displayed broadened maxima. The planar coupling factor was improved by addition of NiO and also increased with increasing sintering time carried out at 105$0^{\circ}C$ Addition of $MnO_2$ yielded a markedly high mechanical quality factor. The space-charge field decreased with the addition of NiO but increased with the addition of $MnO_2$ The planar coupling factor and space-charge field showed same dependence on the additivies. The tetragonality Curie temperature and planar coupling factor of $(Pb_{0.936} La_{0.064})$$(Zr_{0.60}Ti_{0.40})O_3$ were higher than those of $(Pb_{0.936} La_{0.064})$$(Zr_{0.568}NU_{0.032}Ti_{0.40})_{0.984}O_3$ but the grain size lattic parameter dielectric constant dissipation factor mechanical quality factor and space-charge field of the former were lower than those of the latter.

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P-type Electrical Characteristics of the Amorphous La2NiO4+δ Thin Films

  • Hop, Dang-Hoang;Lee, Jung-A;Heo, Young-Woo;Kim, Jeong-Joo;Lee, Joon-Hyung
    • Journal of the Korean institute of surface engineering
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    • v.51 no.4
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    • pp.231-236
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    • 2018
  • We report p-type electrical characteristics of the amorphous $La_2NiO_{4+{\delta}}$ thin films which were sputtered on the glass substrates using an RF sputtering system. As-deposited thin films at room temperature and $300^{\circ}C$ were amorphous in nature. Post-annealing of the thin film samples over $400^{\circ}C$ resulted in the nano-crystallization of the $La_2NiO_{4+{\delta}}$. The electrical properties of the films were much dependent on the oxygen partial pressure, temperature of the post-annealing and sputtering ambient. The as-deposited samples at room temperature show a hole concentration of $7.82{\times}10^{13}cm^{-3}$, and it could be increased as high as $3.51{\times}10^{22}cm^{-3}$ when the films were post-annealed in an oxygen atmosphere at $500^{\circ}C$. Such p-type conductivity behavior of the $La_2NiO_{4+{\delta}}$ films suggests that the amorphous and nano-crystallized $La_2NiO_{4+{\delta}}$ films have potential for the application as p-type semiconductive or conductive materials at low temperatures where material diffusion is limited.

Effect of $LaNiO_3$ electrodes on Structural and Ferroelectric Proerties of $Bi_{3.25}Eu_{0.75}Ti_3O_{12}$ Thin films ($Bi_{3.25}Eu_{0.75}Ti_3O_{12}$ 박막의 구조 및 강유전 특성에 미치는 $LaNiO_3$전극의 영향)

  • Kim, K.T.;Kim, C.I.;Lee, C.I.;Kim, T.A.
    • Proceedings of the KIEE Conference
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    • 2004.11a
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    • pp.75-78
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    • 2004
  • $Bi_{3.25}Eu_{0.75}Ti_3O_{12}$ (BET) thin films were deposited on the $LaNiO_3$ (LNO (100))/Si and Pt/Ti/$SiO_2$/Si substrates by the metal-organic decomposition method. Structural and dielectric properties of BLT thin films for the applications in nonvolatile ferroelectric random access memories were investigated. Both the structure and morphology of the films were analyzed by x-ray diffraction (XRD) and atomic force microscope (AFM). Even at low temperatures $650^{\circ}C$, the BET thinfilms were successfully deposited on LNO bottom electrode and exhibited (001) and (117) orientation. Compared with the Pt electrode films, the BET thin films on the LNO electrode annealed at $650^{\circ}C$ showed better dielectric constantsand remanent polarization. The BET thin films on the LNO electrode for the annealing temperature of $650^{\circ}C$, the remanent polarization Pr and coercive field were $45.6\;C/cm^2$ and 171 kV/cm, respectively.

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