• Journal of Surface Science and Engineering
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• v.22 no.2
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• pp.55-61
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• 1989

A fuel cell which causes electrochemical ratio of conventional with oxygen consists of mainly there parts, such as electrolyte, fuel and oxidant electrode. IN this paper, most efforts were delivered to manufacturing PETE-bonded gas-diffusion electrode, and preparation methods of the porous electrodes has been discussd. A medio temperature, phosphoric acid fuel cell (PAFC) provided with fuel (hydrogen) and oxygen showed oxygen showed excellent performance characteristics with made electrodes. Performance data obtained from hydrgen-oxygen cell were presented to illustrate their properties. It was found that the optimum amounts of platinum in clectrode for hydrgen-oxygen PAFC were about 3mg/cm3 and the PTFE content of gas diffusion layer and catalyst layer were 25% and 15%, respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.340-343
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• 2006

In this paper, heat and mass transfer characteristics through experimental and numerical study are extensively investigated in steam reform ins reactor under given operating conditions. In order to get simulated data at outlet of the reformer, heterogeneous reactor model is incorporated. As the reaction also takes place in porous media, two medium approach is used to take into account thermally non-equilibrium phenomena between catalyst and bulk gas. In steam reforming reaction, heat transfer issue is so significant that geometrical configuration study is also conducted.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.1606-1609
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• 2008

In this paper, we present a novel process for the realization of large area, low cost field emission cathodes. The process makes use of alumina substrates, which are anodically oxidized in order to yield porous structures capable of hosting metal catalyst nanoparticles. By carefully controlling the final stage of the anodisation as well as the electrodeposition conditions, it is possible to fine tune the density of such catalysts in the range of $10^8-10^9/cm^2$. The catalytic growth of CNTs is subsequently performed at low temperature (${\sim}\;600^{\circ}C$ or below, thanks to the use of $H_2O$), using plasma enhanced chemical vapour deposition. There is no lithography need to make the cathode and current densities of ${\sim}\;1mA/cm^2$ are easily obtained.

• Journal of Electrochemical Science and Technology
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• v.3 no.1
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• pp.14-23
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• 2012

Increasing demand of energy, the depletion of fossil fuel reserves, energy security and the climate change have forced us to look upon alternate energy resources. For today's electric vehicles that run on lithium-ion batteries, one of the biggest downsides is the limited range between recharging. Over the past several years, researchers have been working on lithium-air battery. These batteries could significantly increase the range of electric vehicles due to their high energy density, which could theoretically be equal to the energy density of gasoline. Li-air batteries are potentially viable ultra-high energy density chemical power sources, which could potentially offer specific energies up to 3000 $Whkg^{-1}$ being rechargeable. This paper provides a review on Lithium air battery as alternate energy resource for the future.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.697-700
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• 2002

Porous anodic aluminum oxide(AAO) templates prepared by anodizing method were used for growing multiwalled carbon nanotubes(CNTs). AAO templates with the homogeneous pore diameter and length were obtained by two step anodizing technique. Using AAO templates, vertically well-ordered two-dimensional carbon nanotube arrays were fabricated. We investigated the field emission property of CNTs grown using different catalyst metals in vacuum chamber (<$10^{-7}$ Torr) on AAO Template. To explain the different emission property, the surface reaction between catalysts and alumina pores which inserted carbon species of $C_2H_2$ using High resolution transmission electron microscopy (HRTEM) was studied.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.477-480
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• 2002

A new microporous TiO2-pillared layered titanate has been successfully prepared by hybridizing the exfoliated titanate with the anatase TiO2 nano-sol. According to the X-ray diffraction analysis and N2 adsorption-desorption isotherms, the TiO2-pillared layered titanate showed a pillar height of ~2 nm with a high surface area of ~460 m2/g and a pore size of ~0.95 nm, indicating that a microporous pillar structure is formed. Its photocatalytic activity was evaluated by measuring the photodegradation rate of 4-chlorophenol during irradiation of catalyst suspensions in an aqueous solution. An enhancement in activity of ca. 170% was obtained for TiO2-pillared layered titanate compared to that of the pristine compound such as layered cesium titanate.

• Journal of the Korean Society of Combustion
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• v.15 no.2
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• pp.12-18
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• 2010

A numerical analysis was performed to predict the thermo-fluid dynamic characteristics of hydrazine monopropellant reaction in the thruster combustor and nozzle. A 1-D porous model was introduced to simulate catalytic reaction by iridium in the combustor while 2-D axisymmetric analysis was applied to predict the nozzle flow. The chemical species and temperature variations were predicted by changing the injection pressure and mass flow rate and their results were validated by comparison with limited experimental data. The thrust variation with injection pressure could be estimated using the current 1-D combustor modeling.

• New & Renewable Energy
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• v.2 no.4 s.8
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• pp.56-63
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• 2006

In this paper, heat and mass transfer characteristics through experimental and numerical study are extensively investigated in steam reforming reactor under given operating conditions. In order to get simulated data at outlet of the reformer, heterogeneous reactor model is incorporated. As the reaction also takes place in porous media, two medium approach is used to take into account thermally non-equilibrium phenomena between catalyst and bulk gas. From various parametric studies, significance of heat transfer is emphasized in steam reforming reaction.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.85.2-85.2
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• 2011

현재 중온의 고체산화물 연료전지를 위해 다양한 전해질에 대한 연구되었으며 1994년 Ishihara et al.에서 1074K의 온도에서 높은 이온전도도를 갖는 페록스카이 구조를 갖는 LSGM 물질을 발표하였다. Sr과 Mg을 도핑한 Lanthanum gallate는 이온전도도가 1073K에서 0.14S/cm로 YSZ의 5배로 높은 이온전도도를 갖고 있으며 산화환경에서부터 환원환경에서 화학적으로 안정한 특성을 갖고 있다. 또한 LSGM 전해질은 넓은 산소 농도범위에서 안정적인 특성을 갖는 장점을 갖고 있다. 그러나 LSGM은 가장 널리 사용되는 연료극의 Ni 촉매와 고온 소결시 상호확산현상에 의한 2차상을 생성시켜 성능 저감의 원인으로 그 해결방안이 요원한 실정이다. 이에 본 논문에서는 LSGM 전해질에 LSGM scaffold를 형성하고 형성된 scaffold에 연료극 촉매 solution을 infiltration 시켜 저온에서 anode를 형성하여 그 성능을 연구하였다.

• Journal of the Korean Society for Precision Engineering
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• v.33 no.8
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• pp.691-695
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• 2016

This paper covers the investigation of the microscale behavior of Pt nanostrucures fabricated by atomic layer deposition (ALD) at elevated temperature. Nanoparticles are fabricated at up to 70 ALD cycles, while congruent porous nanostructures are observed at > 90 ALD cycles. The areal density of the ALD Pt nanostructure on top of the SiO2 substrate was as high as 98% even after annealing at $450^{\circ}C$ for 1hr. The sheet resistance of the ALD Pt nanostructure dramatically increased when the areal density of the nanostructure decreased below 85 - 89% due to coarsening at elevated temperature.