• 한국수소및신에너지학회논문집
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• 제16권4호
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• pp.372-378
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• 2005

Ni/YSZ ($Y_2O_3$-stabilized $ZrO_2$) composite powder for a cathode material in high temperature electrolysis(HTE) was synthesized by a mechanical alloying method with Ni and YSZ powder. Microstructure of the composite and cell thickness for HTE reaction has been analyzed with various techniques of XRD, SEM to investigate effects of fabrication conditions. Employing the composite material, furthermore, the unit cell for HTE has been studied to evolve hydrogen from water. XRD patterns showed that the composites after wet mechanical alloying were composed of respective nano-sized crystalline Ni and YSZ. While ethanol as additive for mechanical alloying increased to $20\;{\mu}m$ of average particle size of the composites, alpha-terpineol effectively decreased to sub-micro size of that. This study has been found out the evolution of hydrogen by HTE reaction employing the fabricated cathode material, showing 1.4 ml/min of $H_2$ generation rate as increasing $20\;{\mu}m$ of cathode thickness.

• 한국수소및신에너지학회논문집
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• 제17권2호
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• pp.181-192
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• 2006

PEC전지 전극으로 사용될 수 있는 CdSe는 수용액상에서 광부식이 심하기 때문에 투명한 보호막이 필요하다. TiO2는 광부식이 심한 광전극의 보호막으로 적당하며 이 논문에서 화학적 방법(전기증착과 화학조증착)을 이용하여 산성용액이나 알칼리용액에서 TiO2 박막을 제조하여 광흡수나 광전류를 측정하였다. XRD를 이용해서 제조된 TiO2 박막의 결정성을 확인하였으며 막의 표면특성은 SEM으로 측정하였으며 광흡수 특성이 관찰되었다. 제조된 TiO2 박막의 광전류는 100 mw/cm2의 광세기를 가지는 제논 램프를 이용하여 측정하였다. CdSe에 TiO2박막을 코팅했을 때의 CdSe막의 광흡수와 광전류를 측정하여 TiO2 코팅효과를 관찰하였다.

• 한국전기전자재료학회논문지
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• 제26권7호
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• pp.563-566
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• 2013

We investigated the variation of anion exchange membrane of hydrogen generator of alkaline electrolysis. We detected the variation of elements and change of anion exchange membrane using EDS and FE-SEM. We detected two different sites of membrane because of different structure of membrane. $Sp_1$ shows that the distribution ratio of C, O, Al is 98% very higher than $Sp_2$ of 78%. Especially, the main elements of STS316 which is P, S, Fe, Ni were more detected at $Sp_2$ than $Sp_1$. We think that this result depends on the structure of membrane. This also affect the resistance, lifetime of membrane and decrease the efficiency of hydrogen production. We hope that this article is a foundation of developing of hydrogen production technology.

• 한국수소및신에너지학회논문집
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• 제34권6호
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• pp.657-666
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• 2023

In this study, experiments and numerical analysis were conducted to investigate the exhaust gas flow in a common exhaust system of multiple solid oxide fuel cells. The system was fabricated based on KGS code and operated within a pressure range of 0.12 kPa, with flow rates ranging from 79.1 to 103.4 L/min. Numerical modeling was validated with a mean absolute error of 3.8% for pressure results. The study assessed the impact of changes in area ratio and emergency stops on pressure distribution, velocity vectors, and wall shear stress. The findings revealed no significant factors causing high differential pressure or backflow.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3477-3480
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• 2012

• Journal of Welding and Joining
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• 제32권5호
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• pp.13-20
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• 2014

A brief overview is given of the corrosion and hydrogen diffusion behaviors of high strength pipe steel in sour environment. Firstly, hydrogen adsorption and diffusion mechanism of the pipe steel is introduced. Secondly, the effect of iron sulfide film precipitated as a result of the corrosion reaction on the steel surface on hydrogen reduction reaction and subsequent hydrogen permeation through the steel is discussed. Moreover, the hydrogen diffusion behavior of the pipe steel under tensile stress in both elastic and plastic ranges is reviewed based on a number of experimental permeation data and theoretical models describing the hydrogen diffusion and trapping phenomena in the steel. It is hoped that this paper will result in significant academic contributions in the field of corrosion and hydrogen related problems of the pipe steel used in sour environment.

• 한국수소및신에너지학회논문집
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• 제23권2호
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• pp.191-197
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• 2012

The hydrogen storage is one of the key technologies to achieve the successful hydrogen economy and a chain to connect hydrogen production to its utilization. In this paper, characteristics and strong candidates of hydrogen storage technologies were analyzed from the objective information of patents. Also, the hydrogen storage technology trends and gaps were assessed using statistical or qualitative analysis. In this study the patents applied in Korea, Japan, US and EU from 10 or 20 years ago to 2011 were analyzed. The result of patent analysis could be used for developing or searching for promising technology of the hydrogen storage.

• 한국수소및신에너지학회논문집
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• 제16권4호
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• pp.324-333
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• 2005

The kinetics of external hydrogen embrittlememt is considered. The equation of the crack growth rate (CGR) is derived from modification of the model developed by Wilkinson and Vitek. After calculation of hydrogen pressure build-up in the void, the effect of the internal hydrogen pressure on the void growth is added. The CGR is expressed by two terms. One is the term dependent on the critical stress, which is exactly same as Wilkinson and Vitek. The other is term dependent on the pressure of the hydrogen in void.

• 멤브레인
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• 제21권4호
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• pp.345-350
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• 2011

보론이 도프된 바나듐 합금 분리막은 아직까지 연구된 적이 없다. 본 연구에서는 팔라듐이 코팅된 새로운 $V_{99.8}B_{0.2}$ 조성의 합금 분리막을 합성하여 수소 투과 특성 및 화학적 안정성에 대하여 연구를 수행하였다. 순수 수소, 수소와 이산화탄소의 혼합가스를 $400^{\circ}C$, 절대압력 1.0~3.0 bar에서 공급하여 수소 투과 특성을 알아보았다. 순수 수소를 공급하여 측정한 결과 0.5 mm 두께의 분리막은 최대 $48.5mL/min/cm^2$의 투과량을 보였다. 본 연구 결과는 수성가스 전이반응(WGS)에서 생성된 수소를 분리할 수 있는 비 팔라듐계 수소 분리막의 합성에 새로운 방향을 제시하고 있다.

• 한국수소및신에너지학회논문집
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• 제33권1호
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• pp.67-76
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• 2022

We developed a technology that can measure the hydrogen uptake and diffusivity of rubber materials by using the volumetric analysis method and diffusivity analysis program through the measurement of the water level in the graduated cylinder. In this method, hydrogen gas is charged at a certain pressure for a certain period of time for a rubber material exposed to a high-pressure hydrogen gas environment, and then the pressure is reduced to measure the change in the water level in the graduated cylinder in real time, and based on the measured value, it is a technology that can evaluate hydrogen uptake and diffusivity using diffusivity analysis program. Using this method, the hydrogen uptake and diffusivity of the NBR material were measured with respect to the change in the type and weight ratio of the filler used to improve the physical properties of the rubber material. In addition, uncertainty analysis was performed on the diffusivity measurement method.