• 제목/요약/키워드: Lanthanum nickel oxide

검색결과 8건 처리시간 0.022초

The Enhanced Physico-Chemical and Electrochemical Properties for Surface Modified NiO Cathode for Molten Carbonate Fuel Cells (MCFCs)

  • Choi, Hee Seon;Kim, Keon;Yi, Cheol-Woo
    • Bulletin of the Korean Chemical Society
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    • 제35권5호
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    • pp.1305-1311
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    • 2014
  • The nickel oxide, the most widely used cathode material for the molten carbonate fuel cell (MCFC), has several disadvantages including NiO dissolution, poor mechanical strength, and corrosion phenomena during MCFC operation. The surface modification of NiO with lanthanum maintains the advantages, such as performance and stability, and suppresses the disadvantages of NiO cathode because the modification results in the formation of $LaNiO_3$ phase which has high conductivity, stability, and catalytic activity. As a result, La-modified NiO cathode shows low NiO dissolution, high degree of lithiation, and mechanical strength, and high cell performance and catalytic activity in comparison with the pristine NiO. These enhanced physico-chemical and electrochemical properties and the durability in marine environment allow MCFC to marine application as a auxiliary propulsion system.

$La_2O_3$와 NiO의 혼합물로부터 $LaNiO_3$의 메카노케미칼 합성 (Mechanochemical synthesis of $LaNiO_3$ from mixtures of $La_2O_3$ and NiO)

  • 김대영;서병준;손세모;김강언;정수태
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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    • pp.621-624
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    • 2002
  • Lanthanum nickel oxide$(LaNiO_3)$ powders have been prepared via a mechanochemical processing without any additional heat treatment. When a mixed lanthanum and nickel oxide was mechanically activated for 6 hours with 450 rpm, a stable and single phase perovskite powder was successfully synthesized and its crystallite size of about 90 nm is calculated by using the Scherrer equation.

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기공전구체를 이용한 고체전해질 연료전지의 동시소성 연구 (Co-firing of Solid Oxide Fuel Cell Using Pore Former)

  • 문지웅;이홍림;김구대;김재동;이해원
    • 한국세라믹학회지
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    • 제35권3호
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    • pp.273-279
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    • 1998
  • Unite cell of soid oxide fuel cell (SOFC) that consists of a dense yttria-stabilized zirconia(YSZ) electrolyte a porous nickel-YSZ cermet anode and a porous strontium- doped lanthanum manganate(LSM) cathod was fabricated from using pore former through co-firing technique. Initial sintering shrinkage rates of each layer were identified for fabricating SOFC. Heterogenous sintering was very effective in tailoring shrinkage rate for three layers. The powder tailoring necessary for shrinkage rate matching are as follows ; electrolyte of 60% TZ8YS/ 40% TZ8Y mixture anode of 51wt% NiO/49 wt% (70wt% TZ8YS/30 wt% UT ZrO2) mixture and cathode of 80% LSM/20% UT ZrO2 mixture . The overall sintering shrinkage rate differences of three layers using these compositions were maintained in a few percent.

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Chemical Solution Deposition of PZT/Oxide Electrode Thin Film Capacitors and Their Micro-patterning by using SAM

  • Suzuki, Hisao
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.907-912
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    • 2005
  • Micro-patterns of $Pb(Zr_{0.53}Ti_{0.47})O_3$, PZT, thin films with a MPB composition were deposited on $Pt/Ti/SiO_2/Si$ substrate from molecular-designed PZT precursor solution by using self-assembledmonolayer(SAM) as a template. This method includes deposition of SAM followed by the optical etching by exposing the SAM to the UV-light, leading to the patterned SAM as a selective deposition template. The pattern of SAM was formed by irradiating UV-light to the SAM on a substrate and/or patterned PZT thin film through a metal mask for the selective deposition of patterned PZT or lanthanum nickel oxide (LNO) precursor films from alkoxide-based precursor solutions. As a result, patterned ferroelectric PZT and PZT/LNO thin film capacitors with good electrical properties in micrometer size could be successfully deposited.

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이중 페로브스카이트 촉매 PrBaMn2O5+δ의 고온전기분해조(Solid Oxide Electrolysis Cell) 연료극 촉매로 적용 가능성에 대한 연구 (Study on Possibility of PrBaMn2O5+δ as Fuel Electrode Material of Solid Oxide Electrolysis Cell)

  • 권영진;김동연;배중면
    • 한국군사과학기술학회지
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    • 제20권4호
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    • pp.491-496
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    • 2017
  • The hydrogen($H_2$) is promising energy carrier of renewable energy in the microgrid system such as small village and military base due to its high energy density, pure emission and convenient transportation. $H_2$ can be generated by photocatalytic water splitting, gasification of biomass and water electrolysis driven by solar cell or wind turbine. Solid oxide electrolysis cells(SOECs) are the most efficient way to mass production due to high operating temperature improving the electrode kinetics and reducing the electrolyte resistance. The SOECs are consist of nickel-yttria stabilized zirconia(NiO-YSZ) fuel electrode / YSZ electrolyte / lanthanum strontium manganite-YSZ(LSM-YSZ) air electrode due to similarity to Solid Oxide Fuel Cells(SOFCs). The Ni-YSZ most widely used fuel electrode shows several problems at SOEC mode such as degradation of the fuel electrode because of Ni particle's redox reaction and agglomeration. Therefore Ni-YSZ need to be replaced to an alternative fuel electrode material. In this study, We studied on the Double perovskite $PrBrMnO_{5+{\delta}}$(PBMO) due to its high electric conductivity, catalytic activity and electrochemical stability. PBMO was impregnated into the scaffold electrolyte $La_{0.8}Sr_{0.2}Ga_{0.85}Mg_{0.15}O_{3-{\delta}}$(LSGM) to be synthesized at low temperature for avoiding secondary phase generated when it exposed to high temperature. The Half cell test was conducted at SOECs and SOFCs modes.

Characteristics of LaCo1-xNixO3-δ Coated on Ni/YSZ Anode using CH4 Fuel in Solid Oxide Fuel Cells

  • Kim, Jun Ho;Jang, Geun Young;Yun, Jeong Woo
    • Journal of Electrochemical Science and Technology
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    • 제11권4호
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    • pp.336-345
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    • 2020
  • Nickel-doped lanthanum cobalt oxide (LaCo1-xNixO3-δ, LCN) was investigated as an alternative anode material for solid oxide fuel cells. To improve its catalytic activity for steam methane reforming (SMR) reaction, Ni2+ was substituted into Co3+ lattice in LaCoO3. LCN anode, synthesized using the Pechini method, reacts with yttria-stabilized zirconia (YSZ) electrolyte at high temperatures to form an electrochemically inactive phase such as La2Zr2O7. To minimize the interlayer by-products, the LCN was coated via a double-tape casting method on the Ni/YSZ anode as a catalytic functional layer. By increasing the Ni doping amount, oxygen vacancies in the LCN increased and the cell performance improved. CH4 fuel decomposed to H2 and CO via SMR reaction in the LCN functional layer. Hence, the LCN-coated Ni/YSZ anode exhibited better cell performance than the Ni/YSZ anode under H2 and CH4 fuels. LCN with 12 mol% of Ni (LCN12)-modified Ni/YSZ anode showed excellent long-term stability under H2 and CH4 conditions.

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

  • 구현주;이광순;안운선
    • 대한화학회지
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    • 제39권9호
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    • pp.685-691
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    • 1995
  • 결정 분자 궤도함수[EHTB]를 계산할 수 있는 VAX 컴퓨터용 EHMACC와 EHPC 프로그램을, 마이크로-소프트 포트란을 이용하는 PC로 계산할 수 있도록 변환하였다. 이 프로그램을 이용하여 perovskit 구조의 $LaNiO_3$ 단위세포와 ($2{\times}2{\times}1$)으로 확장된 구조에 대한 띠 구조를 계산한 결과, ${\Gamma}{\rightarrow}H,\;H{\rightarrow}N$$N{\rightarrow}{\Gamma}$ 방향(2차원)에서는 bend gap이 0.35eV인 반도체의 성질을 나타내고, ${\Gamma}{\rightarrow}P$$P{\rightarrow}N$ 방향(3차원)에서는 금속성의 성질을 나타내었다. 또 이들 결정에 관한 DOS와 COOP를 고찰한바, $LaNiO_3$에서 산소원자의 DOS는 니켈원자의 결함보다는 산소원자의 위치에 영향을 받아 서로 다른 종류의 산소원자로 존재할수 있음을 알았다.

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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
    • 한국표면공학회지
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    • 제51권4호
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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.