• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2003년도 전지기술심포지움
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• pp.1-18
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• 2003

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2003년도 추계총회 및 학술발표회
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• pp.22-22
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• 2003

• Bulletin of the Korean Chemical Society
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• 제33권12호
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• pp.4247-4250
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• 2012

• Journal of Electrochemical Science and Technology
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• 제9권1호
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• pp.78-83
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• 2018

In this study, we investigated the composition of an electrolytic Fe phosphide at different synthesis temperatures. We found that the ratio of Fe in the electrodeposit increases with synthesis temperature, whereas the oxygen content introduced into the electrodeposit by the atmospheric oxidation of Fe decreases. The aim of this study was to identify the reason for this effect. For this purpose, the ratio of Fe and P in the electrodeposits prepared at different temperatures was analyzed in depth. In addition, the types and ratios of Fe phosphide phases were considered. It was proved that with increase in temperature, a significant amount of Fe reacted with P to form Fe phosphide phases, and consequently, the amount of residual pure Fe that would react directly with oxygen decreased.

• Journal of Electrochemical Science and Technology
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• 제3권3호
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• pp.135-142
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• 2012

Over the past few years, $LiFePO_4$ has been actively studied as a cathode material for lithium-ion batteries because of its advantageous properties such as high theoretical capacity, good cycle life, and high thermal stability. However, it does not have a very good power capability owing to the low lithium-ion diffusivity and poor electronic conductivity. Reduction in particle size of $LiFePO_4$ to the scale of nanometers has been found to dramatically enhance the above properties, according to many earlier reports. However, because of the intrinsically low tap density of nanomaterials, it is difficult to commercialize this method. Many studies are being carried out to improve the volumetric energy density of this material and many methods have been reported so far. This paper provides a brief summary of the synthesis methods and electrochemical performances of micro-spherical $LiFePO_4$ having high volumetric energy density.

• 한국수소및신에너지학회논문집
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• 제30권6호
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• pp.549-555
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• 2019

Electrocatalysis of oxygen reduction reaction (ORR) using Pt nanoparticles or bimetal on carabon was studied. Currently, the best catalyst is platinum, which is a limited resource and expensive to commercialize. In this paper, we investigated the cheaper and more active electrocatalysts by making Pt nanoparticles and adding 3D transition metal such as copper. Electrocatalysts were obtained by chemical reduction based on ethylene glycol solutions. Elemental analysis and particle size were confirmed by XRD and TEM. The electrochemical surface area (ECSA) and activity of the catalyst were determined by electrochemical techniques such as cyclic voltammetry and linear sweep voltammetry method. The commercialized Pt support on carbon (Pt/C, JM), synthesis Pt/C and synthesis Pt3Cu1 alloy nanoparticles supported on carbon were compared. We confirmed that the synthesized Pt3-Cu1/C has high electrochemical performance than commercial Pt/C. It is expected to develop an electrocatalyst with high activity at low price by increasing the oxygen reduction reaction rate of the fuel cell.

• Journal of Electrochemical Science and Technology
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• 제12권2호
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• pp.257-265
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• 2021

In this study, we report niobium (Nb) with hierarchical porous structure produced by a one-pot, HF-free electrochemical etching process. It is proved experimentally that a well-defined hierarchical porous structure is produced from the combination of a limited repetition of pulse etching and high concentration of aggressive anion (i.e., SO₄^2-), which results in hierarchical pores with high order over 3. A formula is derived for the surface area of porous Nb as a function of the hierarchical order of pores while the experimental surface area is estimated on the basis of the electrochemical gas evolution rate on porous Nb. From the comparison of the theoretical and experimental surface areas, an in-depth understanding was gained about porous structure produced in this work in terms of the actual pore shape and hierarchical pore order.

• Korean Chemical Engineering Research
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• 제52권1호
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• pp.58-62
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• 2014

본 연구에서는 Pt/GDC/Pt 셀을 이용하여 상압에서 물과 질소로부터 전기화학적으로 암모니아를 합성하는 연구를 수행하였다. 수분이 포화된 질소분위기에서 작동온도($400{\sim}600^{\circ}C$)와 전압(OCV(Open Circuit Voltage)~1.2 V)에 대한 전기화학적 특성 평가를 수행하였고, 암모니아 합성량을 정량 분석하였다. 정전압 하에서 작동온도의 증가에 따라 인가 전류의 증가로 암모니아 합성량은 증가하였으나, Pt 전극에서 암모니아 합성에 필요한 질소의 화학적 해리 흡착 반응의 한계로 패러데이 효율(faradaic efficiency)은 감소하였다. $600^{\circ}C$에서 최대 암모니아 합성량인 $3.67{\times}10^{-11}mols^{-1}cm^{-2}$(6.7 mA) 얻었고 패러데이 효율은 0.1%이다.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 1999년도 제3회 총회 및 추계학술발표회
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• pp.65-65
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• 1999

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2002년도 연료전지심포지움 2002논문집
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• pp.201-202
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• 2002