• 한국재료학회지
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• 제28권6호
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• pp.330-336
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• 2018

In this study, a membrane electrode assembly(MEA) composed of three electrodes(anode, cathode, and reference electrode) is designed to investigate the effects of methanol concentration on the overpotentials of anode and cathode in direct methanol fuel cells(DMFCs). Using the three-electrode cell, in-situ analyses of the overpotentials are carried out during direct methanol fuel cell operation. It is demonstrated that the three-electrode cell can work effectively in transient state operating condition as well as in steady-state condition, and the anode and cathode exhibit different overpotential curves depending on the concentration of methanol used as fuel. Therefore, from the real-time separation of the anode and cathode overpotentials, it is possible to more clearly prove the methanol crossover effect, and it is expected that in-situ analysis using the three-electrode cell will provide an opportunity to obtain more diverse results in the area of fuel cell research.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.20-23
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• 2009

The efficacy improvement issues in a unit discharge cell have been approached from the structural considerations. The tested cell designs include (a) a coplanar type with annular auxiliary electrode buried in barrier ribs, (b) a coplanar type with split auxiliary electrodes also burred in barrier ribs and (c) a coaxial type with a floating electrode stacked on the base electrode. From spatiotemporally resolved optical images of near-IR emission taken by a gated-ICCD camera and relative VUV emission intensity estimated by laser absorption spectroscopy, the differences in the discharge and light emission performances of those three cell types have been compared and discussed.

• Journal of Microbiology and Biotechnology
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• 제17권1호
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• pp.110-115
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• 2007

Electrochemically active bacteria were successfully enriched in an electrochemical cell using a positively poised working electrode. The positively poised working electrode (+0.7 V vs. Ag/AgCl) was used as an electron acceptor for enrichment and growth of electrochemically active bacteria. When activated sludge and synthetic wastewater were fed to the electrochemical cell, a gradual increase in amperometric current was observed. After a period of time in which the amperometric current was stabilized (generally 8 days), linear correlations between the amperometric signals from the electrochemical cell and added BOD (biochemical oxygen demand) concentrations were established. Cyclic voltammetry of the enriched electrode also showed prominent electrochemical activity. When the enriched electrodes were examined with electron microscopy and confocal scanning laser microscopy, a biofilm on the enriched electrode surface and bacterium-like particles were observed. These experimental results indicate that the electrochemical system in this study is a useful tool for the enrichment of an electrochemically active bacterial consortium and could be used as a novel microbial biosensor.

• 한국에너지공학회:학술대회논문집
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• 한국에너지공학회 2001년도 춘계 학술발표회 논문집
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• pp.215-219
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• 2001

• Macromolecular Research
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• 제10권4호
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• pp.181-186
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• 2002

The displacement of carbon black to polypyrrole as a catalyst supporter in the fuel electrode of a direct methanol fuel cell was investigated. Polypyrrole was obtained as a black powder by the chemical polymerization of pyrrole with three different oxidants. The synthesized polypyrroles were pasted on carbon paper and transformed to the fuel electrodes with electrochemically deposited platinum. The prepared fuel electrode was assembled and mounted in a unit cell using a membrane and cathodic electrode film. In comparison with the carbon black fuel electrode, the performance of the unit cell was analyzed in relation to the state of the catalyst, the type of oxidant, and the morphology of the polypyrrole powder.

• 전기학회논문지P
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• 제63권3호
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• pp.212-217
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• 2014

The electric power output characteristics of magnesium fuel cell were investigated with regard to internal resistance. A equivalent circuit with the series-connected three internal resistance was introduced to analyze of the response to change of power. The power output analysis was employed in order to investigate the effect of internal resistances for the electrolyte concentration, air electrode area, Mg electrode area and distance between the electrodes. It was confirmed that internal resistance is generated by the electrolyte, air electrode and metal electrode, then those Internal resistances had a significant effect on the power output decrease. The power output was a maximum when the load resistance maches the internal resistance of the magnesium fuel cell. The fuel efficiency was only 50% at maximum power output. Higher fuel efficiency was achieved when the load resistance is greater than the internal resistance.

• Journal of Information Display
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• 제3권2호
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• pp.13-18
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• 2002

Numerical simulation is one of the most useful tools to study gas discharge phenomena that occur in alternating current plasma display panel (AC-PDP) cell. Most PDP cell simulations have been performed for two-dimensional cell, is cross-section along the address electrode. We developed a three-dimensional PDP simulator and applied it to a T-shaped electrode cell in order to show the effects of sustain electrode shape that cannot be included in two-dimensional simulation. The dependence of power consumption on electrode shape and area in the simulation showed the same trend as experiment.

• 폴리머
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• 제27권1호
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• pp.46-51
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• 2003

본 연구에서는 적절한 반응 삼상 계면대를 형성하기 위해서 카본블랙과 활성 탄소섬유를 혼합하여 연료전지의 전극을 제조하고, 전극 삼상 계면대의 변화를 고찰하였다. 활성 탄소섬유의 직량비에 따른 백금의 담지량과 백금 입자크기는 각각 원자흡광분석기와 X-선 회절기를 사용하여 분석하였다. 또한 비표면적( $S_{BET}$), 미세기공도 및 기공크기분포(PSD)를 포함하는 전극의 기공구조는 BET를 이용하연 고찰하였으며, 주사전자현미경을 이용하여 전극 삼상 계면대의 형태를 관찰하였다. 실험 결과, 백금의 담지율은 활성 탄소섬유의 첨가에는 큰 영향을 받지 않았다. 반면에, 전극 삼상 계면대는 30% 활성 탄소섬유를 카본블랙에 첨가하였을 경우 더 향상되었는데 이는 촉매의 활성점을 제공하는 미세기공 영역이 증가하였기 때문으로 사료된다.다.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.404-407
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• 2008

Several ITO-less PDP cell structures are presented to improve luminous efficacy. The ITO-less PDP have been applied recently at actual panel manufacture. The influence of ITO-less PDP cell structure on the discharge characteristics has been investigated by using three-dimensional fluid simulation. The variations of electrode geometry parameters such as gap distance, cross bar length, and hump length are investigated for the optimization of cell design.

• Journal of Microbiology and Biotechnology
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• 제9권2호
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• pp.127-131
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• 1999

Anaerobically grown cells of an Fe(III)-reducing bacterium, Shewanella putrefaciens IR-l, were electrochemically active with an apparent reduction potential of about 0.15 V against a saturated calomel electrode in the cyclic voltammetry. The bacterium did not grow fermentatively on lactate, but grew in an anode compartment of a three-electrode electrochemical cell using lactate as an electron donor and the electrode as the electron acceptor. This property was shared by a large number of Fe(III)-reducing bacterial isolates. This is the first observation of a direct electrochemical reaction by an intact bacterial cell, which is believed to be possible due to the electron carrier(s) located at the cell surface involved in the reduction of the natural water insoluble electron acceptor, Fe(III).