• 제목/요약/키워드: Anode effect

검색결과 496건 처리시간 0.022초

플라즈마 반응기구조에 따른 코로나방전 및 NO-NO$_2$ 전환특성에 관한 실험적 연구 (Experimental Study on the Effect of Plasma Reactor Type on Corona Discharge and NO-NO2 Conversion Characteristics)

  • 박용성;전광민
    • 한국자동차공학회논문집
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    • 제10권6호
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    • pp.65-71
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    • 2002
  • Characteristics of corona discharge of the different types of the plasma reactors which are cone-hole and cone-plate is investigated experimentally. The discharge starts at lower voltage for the cathode corona than the anode corona and spark occurs at higher voltage for the cathode corona. And the cathode corona makes more stable discharge than the anode corona. The effect of the base gas in corona discharge for different O$_2$/N$_2$ concentrations is related with the gas molecular weight. The discharge for the smaller molecular weight gas occurs easier than for the high molecular weight gas. The discharge current decreases with the increase of oxygen concentration and it increases more sharply for anode corona than for cathode corona as discharge voltage increases after corona onset voltage. NO-NO$_2$ conversion increases with the energy density of corona discharge and the addition of O$_2$ in a base N$_2$ gas.

Microelectromechnical system 소자를 위한 박막형 2차전지용 $SnO_2$ 음극박막의 충방전 특성 평가 (Charge/Discharge Characteristics of $SnO_2$ thin film as an anode of thin film secondary battery for microelectromechanical system device)

  • 남상철;조원일;전은정;신영화;윤영수
    • 한국진공학회지
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    • 제9권1호
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    • pp.36-41
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    • 2000
  • $SnO-2$ thin films for thin film secondary battery anode were deposited n glass substrate with stain-less steel collector and charge/discharge experiments were conducted to investigate feasibility of $SnO-2$ thin film as a new anode material. The as-deposited films were pure $SnO-2$ phase which is not related to deposition condition. The grain size on the surface of as-deposited films increased with increase of oxygen partial pressure. However, the grain size did not show any change above oxygen partial pressure of 80:20. The surface roughness of the as-deposited films increased after decreasing because of resputtering effect of oxygen negative ion in plasma. All films showed typical $SnO-2$ anode characteristics which has a side effect at the first cycle, which is not related to the deposition condition. The charge/discharge experiments of 200cycles indicated that capacity of $SnO-2$ films depended on oxygen contents and surface roughness. The cycle characteristics was determined by initial charge/discharge reaction. The $SnO-2$ film with low initial capacity showed more stable cycle characteristics than film with high initial capacity.

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Effect of Thermal Treatment Temperature on Lifespan of Conductive Oxide Electrode

  • Yoo, Y.R.;Chang, H.Y.;Jang, S.G.;Nam, H.S.;Kim, Y.S.
    • Corrosion Science and Technology
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    • 제6권2호
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    • pp.44-49
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    • 2007
  • Dimensionally stable anodes have been widely used to cathodically protect the metallic materials in corrosive environments including concrete structure as the insoluble anode. Lifespan of the anode for concrete construction can be determined by NACE TM0294-94 method. Lifespan of conductive oxide electrode would be affected by thermal treatment condition in the process of sol-gel coatings. This work aims to evaluate the effect of thermal treatment temperature on the lifespan of the $RuO_{2}$ electrode. $450^{\circ}C$ treated conductive oxide electrode showed the excellent properties and its lifespan was evaluated to be over 88 years in 3% NaCl, 4% NaOH, and simulated pore water. This behavior was related to the formation of $RuO_{2}$.

고체산화물 연료전지의 운전 조건에 따른 니켈 전극 황 피독 현상 (Sulfur Poisoning of Ni Anode as a Function of Operating Conditions in Solid Oxide Fuel Cells)

  • 이호성;이현미;임형태
    • 대한금속재료학회지
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    • 제56권12호
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    • pp.893-899
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    • 2018
  • In the present study, we investigated the sulfur poisoning of the Ni anode in solid oxide fuel cells (SOFCs) as a function of operating conditions. Anode supported cells were fabricated, and sulfur poising tests were conducted as a function of current density, $H_2S$ concentration and humidity in the anode gas. The voltage drop was significant under the higher current density (${\sim}714mA/cm^2$) condition, while it was much reduced under the lower current density (${\sim}389mA/cm^2$) condition, at 100 ppm of $H_2S$. A secondary voltage drop, which occurred only at the high current density, was attributed to Ni oxidation in the anode. Thus, operation at high current density with high $H_2S$ concentration may lead to permanent deterioration in the anode. The effect of water content (10%) on the sulfur poisoning was also investigated through a constant current test (${\sim}500mA/cm^2$) at 10 ppm of $H_2S$. The cell operating with 10% wet anode gas showed a much smaller initial voltage drop, in comparison with a dry anode gas. The present study indicates that operating conditions, such as gas humidity and current density, should be carefully taken into account, especially when fuel cells are operated with $H_2S$ containing fuel.

Effect of the LiF anode interfacial layer on polymer light emitting diodes

  • Sohn, Sun-Young;Lee, Dae-Woo;Park, Keun-Hee;Jung, Dong-Geun;Kim, H.M.;Manna, U.;Yi, J.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1056-1058
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    • 2005
  • Electrical and optical characteristics of MEH-PPV-based PLEDs with the LiF anode interfacial layer were investigated. The maximum luminance efficiency of the device with a LiF anode interfacial layer of 1-nm-thick was 3.0 lm/W, which is higher than 1.97 lm/W of the device without a LiF layer. By inserting LiF, excess injected holes from ITO anode can be blocked and hence the recombination ratio of electrons and holes can be increased in the emitting layer to improve device efficiency.

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용융탄산염 연료전지의 양극 대체재료의 개발에 관한 연구 (A Study on the Development of Anode Material for Molten Carbonate Fuel Cell)

  • 황응림;김선지;강성군
    • 에너지공학
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    • 제2권3호
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    • pp.293-299
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    • 1993
  • 용융탄산염연료전지(MCFC)용 다공성 Ni 양극에 3~10 wt% Al를 첨가하여 tape casting 법으로 제조된 Ni-Al 양극의 전기화학적성능 및 구조적안정성이 조사되었다. 본 연구에서 제조된 양극의 전기화학적 성능이 $650^{\circ}C$, MCFC 양극분위기(80% H$_2$+20% $CO_2$)를 모사한 half-cell 에서 양분극 특성으로 평가되었는데, 전류밀도 150 ㎃/$\textrm{cm}^2$ 에서의 분극전압은 약 100 ㎷로 실용전지의 양극으로서 가능성을 보였다. Ni-Al 양극의 소결과 creep에 대한 저항성은 Ni 양극에 비해 증가되었는데, 이는 Ni 입자 표면에 형성된 $Al_2$O$_3$의 영향으로 판단되었다.

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Pulsed Wire Evaporation(PWE) Method으로 제조된 나노 NiO 분말의 SOFC 연료극 기능성층으로의 적용 (The Effect of Using Nano NiO Powder Made by Pulsed Wire Evaporation (PWE) Method on SOFC Anode Functional Layer)

  • 김혜원;김동주;박석주;임탁형;이승복;신동렬;윤순길;송락현
    • 한국수소및신에너지학회논문집
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    • 제20권6호
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    • pp.485-491
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    • 2009
  • In present work, NiO/YSZ anode functional layer was prepared by nano NiO powder and 8YSZ powder. The nano NiO powders were made by Pulsed wire evaporation (PWE) method. Nano NiO- YSZ functional layer was sintered at the temperature of $900-1400^{\circ}C$. The prepared functional layer was characterized by scanning electron microscopy (SEM) and electrochemical impedance spectroscopy. The nano NiO- YSZ anode functional layer sintered at $1300^{\circ}C$ shows the lowest polarization resistance. Nano NiO- YSZ anode functional layer shows about two times smaller polarization resistance than the anode functional layer made by commercial NiO-YSZ powders. Based on these experimental results, it is concluded that the nano NiO-YSZ cermet is suitable as a anode functional layer operated at $800^{\circ}C$.

LSGM계 음극지지형 고체산화물 연료전지에 적용된 LDC 완충층의 효과 (Effect of the LDC Buffer Layer in LSGM-based Anode-supported SOFCs)

  • 송은화;정태주;김혜령;손지원;김병국;이종호;이해원
    • 한국세라믹학회지
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    • 제44권12호
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    • pp.710-714
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    • 2007
  • LSGM$(La_{0.8}Sr_{0.2}Ga_{0.8}Mg_{0.2}O_{3-{\delta}})$ is the very promising electrolyte material for lower-temperature operation of SOFCs, especially when realized in anode-supported cells. But it is notorious for reacting with other cell components and resulting in the highly resistive reaction phases detrimental to cell performance. LDC$(La_{0.4}Ce_{0.6}O_{1.8})$, which is known to keep the interfacial stability between LSGM electrolyte and anode, was adopted in the anode-supported cell, and its effect on the interfacial reactivity and electrochemical performance of the cell was investigated. No severe interfacial reaction and corresponding resistive secondary phase was found in the cell with LDC buffer layer, and this is due to its ability to sustain the La chemical potential in LSGM. The cell exhibited the open circuit voltage of 0.64V, the maximum power density of 223 $mW/cm^2$, and the ohmic resistance of $0.17{\Omega}cm^2$ at $700^{\circ}C$. These values were much improved compared with those from the cell without any buffer layer, which implies that formation of the resistive reaction phases in LSGM and then deterioration of the cell performance is resulted mainly from the La diffusion from LSGM electrolyte to anode.

Effect of Cl2 on Electrodeposition Behavior in Electrowinning Process

  • Kim, Si Hyung;Kim, Taek-Jin;Kim, Gha-Young;Shim, Jun-Bo;Paek, Seungwoo;Lee, Sung-Jai
    • 한국방사성폐기물학회:학술대회논문집
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    • 한국방사성폐기물학회 2017년도 추계학술논문요약집
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    • pp.73-73
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    • 2017
  • Pyroprocessing at KAERI (Korea Atomic Energy Research Institute) consists of pretreatment, electroreduction, electrorefining and electrowinning. SFR (Sodium Fast Reactor) fuel is prepared from the electrowinning process which is composed of LCC (Liquid Cadmium Process) and Cd distillation et al. LCC is an electrochemical process to obtain actinides from spent fuel. In order to recover actinides inert anodes such as carbon material are used, where chlorine gas ($Cl_2$) evolves on the surface of the carbon material. And, stainless steel (SUS) crucible should be installed in large-scale electrowinning system. Therefore, the effect of chlorine on the SUS material needs to be studied. LiCl-KCl-$UCl_3$-$NdCl_3$-$CeCl_3$-$LaCl_3$-$YCl_3$ salt was contained in 2 kinds of electrolytic crucible having an inner diameter of 5cm, made of an insulated alumina and an SUS, respectively. And, three kinds of electrodes such as cathode, anode, reference were used for the electrochemical experiments. Both solid tungsten (W) and LCC were used as cathodes. Cd of 45 g as the cathode material was contained in alumina crucibles for the deposition experiments, where the crucible has an inner diameter of 3 cm. Glassy carbon rod with the diameter of 0.3 cm was employed as an anode, where shroud was not used for the anode. A pyrex tube containing LiCl-KCl-1mol% AgCl and silver (Ag) wire having a diameter of 0.1cm was used as a reference electrode. Electrodeposition experiments were conducted at $500^{\circ}C$ at the current densities of $50{\sim}100mA/cm^2$. In conclusion, Fe ions were produced in the salt during the electrodeposition by the reaction of chlorine evolved from the anode and Fe of the SUS crucible and thereby LCC system using SUS crucible showed very low current efficiencies compared with the system using the insulated alumina crucible. Anode shroud needs to be installed around the glassy carbon not to influence surrounding SUS material.

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직접 수소화붕소나트륨/과산화수소 연료전지의 산화극 연료 조성에 관한 연구 (A Study on Anode Fuel Composition of Direct Borohydride/Hydrogen Peroxide Fuel Cell)

  • 이태훈;유수상;오택현
    • 한국수소및신에너지학회논문집
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    • 제32권6호
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    • pp.514-523
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    • 2021
  • This study investigated the effect of anode fuel composition on the performance of direct borohydride/hydrogen peroxide fuel cells (DBHPFCs). The effect of sodium borohydride (NaBH4) and sodium hydroxide (NaOH) concentrations on fuel cell performance was determined through fuel cell tests. Fuel cell performance increased with an increase in the NaBH4 concentration, whereas it decreased with an increase in the NaOH concentration. The anode fuel composition was selected as 10 wt% NaBH4+10 wt% NaOH+80 wt% H2O based on the fuel viscosity, electrochemical reaction rate, and decomposition reaction rate. DBHPFCs were also tested to analyze the effect of operating temperature and operation time on fuel cell performance. The present results can be used as a reference basis to determine operating conditions of DBHPFCs.