• Title/Summary/Keyword: Anode efficiency

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Study on the High Efficiency of Anode Phosphor Electrode for Filed Emission Lamp (II) - Diffused Reflection Layer (전계방출광원용 고효율 에노드 형광막 특성 연구(II) - 난반사막)

  • Lee, Sun-Hee;Kim, Kwang-Bok;Kim, Yong-Won;You, Yong-Chan;Kim, Do-Jin
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2007.05a
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    • pp.89-91
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    • 2007
  • In order to decrease the degradation of phosphor on anode, many kinds of methods try to do coating of phosphor powders and AI metal layer of anode phosphor, In case of direct coating of phosphor powder, thin and uniform coating process are difficult to cover homogeneous in the surface of phosphor powders and given rise to decrease the brightness, Anti-reflection-layer(ARC) with $TiO_2$, $Al_2O_3$, $Y_2O_3$ showed 103[%] the enhancement of brightness in comparable with normal phosphor layer.

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Menadione-Modified Anodes for Power Enhancement in Single Chamber Microbial Fuel Cells

  • Ahmed, Jalal;Kim, Sunghyun
    • Bulletin of the Korean Chemical Society
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    • v.34 no.12
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    • pp.3649-3653
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    • 2013
  • As anode fabrication with different materials has been proven to be a successful alternative for enhancing power generation in the microbial fuel cells, a new approach to improved performance of MFCs with the use of menadione/carbon powder composite-modified carbon cloth anode has been explored in this study. Menadione has formal potential to easily accept electrons from the outer membrane cytochromes of electroactive bacteria that can directly interact with the solid surface. Surface bound menadione was able to maintain an electrical wiring with the trans-membrane electron transfer pathways to facilitate extracellular electron transfer to the electrode. In a single chamber air cathode MFC inoculated with aerobic sludge, maximum power density of $1250{\pm}35mWm^{-2}$ was achieved, which was 25% higher than that of an unmodified anode. The observed high power density and improved coulomb efficiency of 61% were ascribed to the efficient electron shuttling via the immobilized menadione.

Mechanochemical Synthesis of ZnMn2O4 and its Electrochemical Properties as an Anode Material for Lithium-ion Batteries

  • Park, Yoon-Soo;Oh, Hoon;Lee, Sung-Man
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3333-3337
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    • 2011
  • $ZnMn_2O_4$ has been prepared by a mechanochemical process using a mixture of $Mn_2O_3$ and ZnO as starting materials, and investigated as a possible anode material for lithium-ion batteries. The phase evolution and morphologies of the ball-milled and annealed powders are characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) with energy dispersive microanalysis (EDX), respectively. The solid-state reaction for the formation of $ZnMn_2O_4$, under the given experimental conditions, is achieved in a short time (30 min), and the prepared samples exhibit excellent electrochemical performances including an enhanced initial coulombic efficiency, high reversible capacity, and stable capacity retention with cycling.

Effects of Aluminum and Silicon as Additive Materials for the Zinc Anode in Zn-Air Batteries

  • Lee, Yong-Seok;Ryu, Kwang-Sun
    • Journal of the Korean Electrochemical Society
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    • v.21 no.1
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    • pp.12-20
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    • 2018
  • To solve low cycle efficiency of the zinc anode in Zn-air batteries by corrosion, this study examined the effects of Al as a cathodic protection additive to Zn. The Al-mixed Zn anodes were produced by mixing Zn and Al powder (1, 2, and 3 wt. %). To compare the effects of the Al additive, Si was selected under the same conditions. The morphology and elemental composition of the additives in the Zn were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and inductively coupled plasma - mass spectrometry. The anti-corrosion effects of the Al and Si-mixed Zn anodes were examined by linear polarization. Cyclic voltammetry and charge-discharge tests were conducted to evaluate the electrochemical performance of the Al and Si-mixed Zn anodes. As a result, the Al-mixed Zn anodes showed highest corrosion resistance and cycling performance. Among these, the 2 wt.% Al-mixed Zn anodes exhibited best electrochemical performance.

ZnO/ITO anode for organic electro-luminescence devices

  • Jeong, S.H.;Kho, S.;Jung, D.;Boo, J.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.885-886
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    • 2003
  • A bilayer is used as an anode electrode for organic electroluminescent devices. The bilayer consist of an ultrathjn ZnO layer adjacent to an hole-transporting layer and an Indium tin oxide(ITO) outerlayer. We tried to bring low the barrier between the devices as deposited ZnO films on ITO substrates. We fabricated the organic EL structure consisted of Al as cathode, $Al_{2}O_{3}$ as electro transport layer, Alq3 as luminously layer, triphenyl diamine(TPD) as hole transport layer and ZnO(l nm )/ITO(l50 nm) as anode. The result of this experiment was not good compared with the case of using ITO, Nevertheless, at this structure we obtained the lowest turn-on voltage as the value of 19 V and the good brightness (6200 $cd/m^{2}$) of the emission light from the devices. Then the quantum efficiency was to be 1.0%.

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An Effect of the Overlapping with the Anode and Cathode Flow Channel to PEMFC Performance (연료극과 공기극 유로의 겹침이 PEMFC 성능에 미치는 영향)

  • Lee, Ji-Hong;Lee, Myeong-Yong;Lee, Sang-Seok;Lee, Do-Hyung
    • New & Renewable Energy
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    • v.5 no.1
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    • pp.18-25
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    • 2009
  • PEMFC (Proton Exchange Membrane Fuel Cell) is a low temperature fuel cells which are high efficient and clean energy. But it has many problems like economical efficiency or durability. Because of this reason, many researchers challenge various view points. One of challenge is the flow channel design and many researchers develop new flow channel design. In addition to most of them have the anode and cathode's flow channel overlapped almost perfectly. In this case, the electrochemical reaction is almost done by the inertial force of flow. So we study on the effect of the anode and cathode's flow channel which aren't overlapped perfectly, have more diffusion effect, to PEMFC performance using CFD.

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Fuel Cell Performance by the Impedance Method (연료전지의 임피던스방법 적용 연구)

  • Kim, Gwi-Yeol
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2008.06a
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    • pp.510-511
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    • 2008
  • Fuel cell is a modular, high efficient and environmentally energy conversion device, it has become a promising option to replace the conventional fossil fuel based electric power plants. The high temperature fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. And, The research and development for the solid oxide fuel cell have been promoted rapidly and extensively in recent years, because of their high efficiency and future potential. Therefore this paper describes the manufacturing method and characteristics of anode electrode for solid oxide fuel cell, by the way, Ni-YSZ materials are used as anode of high temperature widely. So in this experiments, we investigated the optimum content of Ni, by the impedance characteristics, overvoltage. As a result, the performance of Ni-YSZ anode(40vol%) was better excellent than the others.

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Fuel Cell Performance by the Impedance Method (임피던스법을 적용한 연료전지 성능규명)

  • 김귀열;서장수;박용필;이준응
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.11a
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    • pp.157-159
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    • 2001
  • The molten carbonate fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. However, the MCFC which use strongly corrosive molten carbonate at 650$^{\circ}C$ have many problem. Systematic investigation on corrosion behavior of Fe/20Cr/Ti alloys has been done in (62+38)mol% (Li+K)CO$_3$ melt at 923K by using steady state polarization and electrochemical impedance spectroscopy method. And, The research and development for the solid oxide fuel cell have been promoted rapidly and extensively in recent years, because of their high efficiency and future potential. Therefore this paper describes the manufacturing method and characteristics of anode electrode for SOFC, by the way, Ni-YSZ materials are used as anode of SOFC widely. So in this experiments, we investigated the optimum content of Ni, by the impedance characteristics, overvoltage. As a result, the performance of Ni-YSZ anode(47vo1%) was bettor excellent than the others.

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Fuel Cell Performance by the Impedance Method (임피던스법을 이용한 연료전지의 특성 연구)

  • 서장수;김귀열;명기환;이성일;김용주
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2000.07a
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    • pp.927-933
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    • 2000
  • The molten carbonate fuel cell has conspicuous feature and high potential in being used as an energy converter of various fuel to electricity and heat. However, the MCFC which use strongly corrosive molten carbonate at 650$^{\circ}C$ have many problem. Systematic investigation on corrosion behavior of Fe/20Cr/Ti alloys has been done in (62+38)mol% (Li+K)CO3 melt at 923K by using steady state polarization and electrochemical impedance spectroscopy method. And, The research and development for the solid oxide fuel cell have been promoted rapidly and extensively in recent years, because of their high efficiency and future potential. Therefore this paper describes the manufacturing method and characteristics of anode electrode for SOFC, by the way , Ni-YSZ materials are used as anode of SOFC widely. So in this experiments, we investigated the optimum content of Ni, by the impedance characteristics, overvoltage. As a results, the performance of Ni-YSZ anode(40vo1%) was better excellent than the others.

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Thermally Crosslinked Polyimide Binders for Si-alloy Anodes in Li-ion Batteries

  • Chang, Hyeong-Seok;Ji, Sang-Gu;Rho, Miso;Lee, Byoung-Min;Kim, Sung-Soo;Choi, Jae-Hak
    • Journal of Electrochemical Science and Technology
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    • v.13 no.3
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    • pp.339-346
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    • 2022
  • Silicon (Si) has attracted considerable attention due to its high theoretical capacity compared to conventional graphite anode materials. However, Si-based anode materials suffer from rapid capacity loss due to mechanical failure caused by large volume change during cycling. To alleviate this phenomenon, crosslinked polymeric binders with strong interactions are highly desirable to ensure the electrode integrity. In this study, thermally crosslinked polyimide binders were used for Si-alloy anodes in Li-ion batteries. The crosslinked polyimide binder was found to have high adhesion strength, resulting in enhanced electrode integrity during cycling. Therefore, the Si-alloy anodes with crosslinked polyimide binder provide enhanced electrochemical performance, such as Coulombic efficiency, capacity retention, and cycle stability.