• 한국전기화학회:학술대회논문집
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• 2002.07a
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• pp.251-258
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• 2002

[ $Ni-10wt.\%Cr$ ] green sheet를 불활성분위기로 $900^{\circ}C$까지 승온시킨 다음 부분산화$(P_{H2}/P_{H2O}=10^{-2})$후 $1100^{\circ}C$에서 3시간 환원처리를 시키는 소결공정으로 Ni-Cr 고용체 기지 주변에 작은 $Cr_2O_3$ 알갱이가 고르게 분포하는 anode(Anode Sintered in Partial oxidation - Reduction atmosphere; ASPR)를 제조하였으며, creep 변형률이 $2.8\%$로서 미세구조에 따른 creep 특성의 비교를 위해 기존의 환원분위기에서만 소결시킨 anode(Anode Sintered in Reduction atmosphere only; ASR)의 $11\%$보다 우수한 creep 저항성을 나타내었다. $Cr_2O_3$ 알갱이가 분산된 미세구조른 부분산화 시 Cr과 Ni의 산화속도 및 확산속도의 차이로 인해 형성되는 것으로 사료되며, creep 전${\cdot}$후 ASPR 시편의 SEM 및 기공률 분석결과 매우 안정적으로 그 형상 및 구조를 유지하고 있음을 확인할 수 있었다. 또한 ASPR 시편의 전기전도도는 약 $15\times10^6\;S/m$로서 기존 ASR 시편의 전기전도도와 유사함을 알 수 있었다.

• Resources Recycling
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• v.26 no.4
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• pp.34-41
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• 2017

The effect of Mn(II) concentration on the anodic reactions occurring on a Pb-Ag electrode in sulfuric acid solutions has been studied by potentiostatic oxidation in the potential range of 1.8 to 2.0 V. High oxidation potentials and low initial concentrations of Mn(II) resulted in higher concentrations of soluble Mn(III) ions which were obtained from spectrophotometric analysis of the solution after oxidation. $MnO_2$ was deposited on the electrode by electrochemical oxidation of Mn(II) at 1.8 and 1.9 V, while it was formed by disproportionation of Mn(III) at 2.0 V. No $PbO_2$ was formed in the presence of Mn(II) during potentiostatic oxidation treatment for two hours at 1.8 V. Chemical reduction of $PbO_2$ with Mn(II) led to a decrease in the amount of $PbO_2$ as Mn(II) concentration increased at 1.9 and 2.0 V.

• Transactions of the Korean hydrogen and new energy society
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• v.17 no.1
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• pp.82-89
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• 2006

The redox behaviors of anode-supported flat tube for solid oxide fuel cell has been studied. The mass change of the extruded NiO/YSZ anode flat tube during redox cycling was examined by thermogravimetric analysis(TGA). The result of TGA was shown a rapidly mass change in the range of $455\;-\;670^{\circ}C$ and the reoxidation of the NiO/YSZ anode was almost completed at $750^{\circ}C$. The starting temperature of reoxidation and the maximum temperature of oxidation rate decreased with increasing the reoxidation cycle, which is attributed to the increased porosity caused by volume change. Bending strengths of the NiO/YSZ anode after redox cycling were 96 - 80 MPa and the bending strength decreased slightly with increasing the redox cycle. On the other hand, the bending strength of the NiO/YSZ anode with electrolyte showed 130 MPa after first redox cycling but decreased rapidly with increasing the redox cycle. From the results of the bending test and the microstructure observation, we conclude that the crack initiation of the electrolyte-coated NiO/YSZ anode was induced easily at interface of electrolyte/anode tube and propagated cross the electrolyte.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.3
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• pp.409-421
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• 2012

Ethanolamine (ETA) is mainly used to prevent corrosion of pipe in secondary cooling system of nuclear power plant. Condensed ETA in wastewater could increase COD and T-N when it was emitted to natural water system. Compared to conventional treatments, electrochemical oxidation process using packed bed bipolar electrodes was adopted to treat COD and T-N. According to arrangement of feeder electrode, single packed bed bipolar electrode reactor and multi-paired packed bed bipolar reactor were developed and conventional zero-valent iron (ZVI) was selected as conducting bipolar electrode. Bipolar electrodes were coordinated three-dimensionally in the reactor. The experimental results showed that COD and T-N was little removed in unit system at different pH condition (pH 8 and 11) on 100V. However, in multi-paired system that applied 600V, COD was eliminated 80.85% (anode-cathode-anode, A-C-A) and 85.11% (cathode-anode-cathode, C-A-C), respectively. T-N was also removed 96.88% (A-C-A) and 90.63% (C-A-C), simultaneously. Current efficiency was estimated both single and multi-paired system. At unit bipolar packed bed reactor, current efficiency was almost zero, however in multi-paired system, current efficiency was 300~500% at A-C-A and 250~350% at C-A-C. Current efficiency was over 100% hence it was confirmed that this system is more effective than conventional electrochemical oxidation system.

• Proceedings of the KAIS Fall Conference
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• 2004.11a
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• pp.99-102
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• 2004

Display process has adopted RCA clean, being applied to large area and coped with environmental issue for last ten years. However, the approaching concept of ozonized, hydrogenised, or electrolyzed water cleaning technologies is within RCA clean paradigm. In this work, only electrolyzed anode water was applied to clean particles and organics as well as metals based on Pourbaix concept, and as a test vehicle, MgO particles were introduced to prove the new concept. The electrolyzed anode water is very oxidative with high oxidation reduction potential(ORP) and low in pH of more than 900mV and 3.1, respectively. MgO particles were immerged in the anode water and its weight losses due to dissolution were measured with time. Weight losses were in the ranges of 100 to 500 micrograms in 250m1 anode waters depending on their ORP and pH. Therefore it was concluded that the cleaning radicals in the anode water was at least in the range of 1 to 5E20 ea per 250 ml anode water equivalent to IE18 ea/cm3. Hence it can be assumed that the anode water be applied to display cleaning since 1E10 to IE15 ea/cm3 ranges of contaminants are being treated. In addition, it was observed that anode water does not develop micro-roughness on hydrophobic surface while it does on the native silicon oxide.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.965-974
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• 2022

Platinum anodes are widely used for metal oxides reduction in LiCl-Li₂O, however high-cost and low-corrosion resistance hinder their implementation. NiO-Li₂O ceramics is an alternative corrosion resistant anode material. Anode processes on platinum and NiO-Li₂O ceramics were studied in (80 mol.%) LiCl-(20mol.%)KCl and (80 mol.%)LiCl-(20 mol.%)KCl-Li₂O melts by cyclic voltammetry, potentiostatic and galvanostatic electrolysis. Experiments performed in the LiCl-KCl melt without Li₂O illustrate that a Pt anode dissolution causes the Pt²⁺ ions formation at 3.14 V and 550℃ and at 3.04 V and 650℃. A two-stage Pt oxidation was observed in the melts with the Li₂O at 2.40 ÷ 2.43 V, which resulted in the Li₂PtO₃ formation. Oxygen current efficiency of the Pt anode at 2.8 V and 650℃ reached about 96%. The anode process on the NiO-Li₂O electrode in the LiCl-KCl melt without Li₂O proceeds at the potentials more positive than 3.1 V and results in the electrochemical decomposition of ceramic electrode to NiO and O₂. Oxygen current efficiency on NiO-Li₂O is close to 100%. The NiO-Li₂O ceramic anode demonstrated good electrochemical characteristics during the galvanostatic electrolysis at 0.25 A/cm² for 35 h and may be successfully used for pyrochemical treating of spent nuclear fuel.

• Journal of Energy Engineering
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• v.2 no.3
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• pp.293-299
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• 1993

In order to investigate the effect of Al addition on the electrochemical performance and structural stability of porous Ni anode for molten carbonate fuel cell, porous Ni anodes containing Al up to 10 wt% were fabricated by the tape casting technique. In this study half-cell performance of the anodes was evaluated by anodic polarization in the simulated MCFC anode condition(650$^{\circ}C$ , 80% H$_2$＋20% CO$_2$). At the anodic current of 150 ㎃/$\textrm{cm}^2$, the polarizations for H$_2$oxidation of the anode was about 100 ㎷. The sintering and creep resistance of Ni-Al anodes was higher than those of the pure Ni anode. It was considered that the increase of sintering and creep resistance was due to the formation of Al$_2$O$_3$ on the surface of Ni particles.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1368-1373
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• 2008

An electrochemical reactor was designed and operated to treat the solution containing endocrine disruptive compounds such as phenol and bisphenol A. An experiment involving the electrochemical oxidation of bisphenol A was performed with the use of a dimensionally stable anode (DSA). The apparent current, conductivity, and the gap between cathode and anode were selected as design parameters. The phenol removal rate increased with an increase in apparent current. The bisphenol A removal rate increased with an increase in apparent current efficiency. An increase in the conductivity also led to an increase in the rate of removal of bisphenol A. The gap between cathode and anode did not affect the bisphenol A removal rate or the cathodic current efficiency.

• Journal of Microbiology and Biotechnology
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• v.15 no.1
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• pp.80-85
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• 2005

Electrochemical control of the metabolic flux of W. kimchii sk10 on glucose and pyruvate was studied. The growing cell of W. kimchii sk10 produced 87.4 mM lactate, 69.3 mM ethanol, and 4.9mM lactate from 83.1mM glucose under oxidation condition of the anode compartment, but 98.9 mM lactate, 84.3mM ethanol, and 0.2 mM acetate were produced from 90.8 mM glucose under reduction condition of the cathode compartment for 24 h, respectively. The resting cell of W. kimchii sk10 produced 15.9 mM lactate and 15.2 mM acetate from 32.1 mM pyruvate under oxidation condition of the anode compartment, and 71.3 mM lactate and 3.8 mM acetate from 79.8mM pyruvate under reduction condition of the cathode compartment. The redox balance (NADH/$NAD^+$) of metabolites electrochemically produced from pyruvate was 1.05 and 18.76 under oxidation and reduction conditions, respectively. On the basis of these results, we suggest that the neutral red (NR) immobilized in bacterial membrane can function as an electron channel for the electron transfer between electrode and cytoplasm without dissipation of membrane potential, and that the bacterial fermentation of W. kimchii sk10 can be shifted to oxidized or reduced pathways by the electrochemical oxidation or reduction, respectively.

• Journal of Welding and Joining
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• v.26 no.4
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• pp.50-54
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• 2008

In this research, anode for SOFC has been manufactured from two different kinds of feedstock materials through thermal spraying process and the properties of the coatings were characterized and compared. One kind of feedstock was manufactured from spray drying method which includes nano-components of NiO, YSZ (300 nm) and graphite. And the other is manufactured by blending the micron size NiO coated graphite, YSZ and graphite powders as feedstock materials. Microstructure, mechanical properties and electrical conductivity of the coatings as-sprayed, after oxidation and after hydrogen reduction containing nano composite which is prepared from spray-dried powders were evaluated and compared with the same properties of the coatings prepared from blended powder feedstock. The coatings prepared from the spray dried powders has better properties as they provide larger triple phase boundaries for hydrogen oxidation reaction and is expected to have lower polarization loss for SOFC anode applications than that of the coatings prepared from blended feedstock. A maximum electrical conductivity of 651 S/cm at $800^{\circ}C$ was achieved for the coatings from spray dried powders which much more than that of the average value.