• 한국수소및신에너지학회논문집
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• 제21권5호
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• pp.383-389
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• 2010

Co-B, Co-P-B, Co-Ni-B and Co-Ni-P-B catalysts supported on Ni foam were prepared using electroless plating in the present study. The surface morphology of the catalysts/Ni foam was observed using SEM and EDS analysis. The Co-Ni-P-B/Ni foam catalyst showed the superior performance on hydrogen generation due to the uniform formation of catalyst particles on the Ni foam surface. The characteristics of hydrogen generation with Co-Ni-P-B/Ni foam catalyst was investigated at the variety of $NaBH_4$ and NaOH concentrations. Durability test was performed, resulting in the stable hydrogen generation for 6 hours.

• 한국수소및신에너지학회논문집
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• 제24권1호
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• pp.1-11
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• 2013

Additives such as glycerol, methanol, acetone, and ethanol were used to prevent $NaBO_2$ from precipitation, and their effects on hydrogen generation properties of $NaBH_4$ hydrolysis were investigated. When the concentration of additives was 5 wt%, the additives such as methanol, acetone, and ethanol could not prevent $NaBO_2$ precipitation. Although glycerol prevented $NaBO_2$ precipitation, conversion efficiency decreased to 78.0% due to its viscosity. Based on test results, hydrogen generation tests were also performed at various concentration of glycerol and methanol to investigate the concentration effects on hydrogen generation properties. As the concentration of glycerol increased from 1 wt% to 3 wt%, conversion efficiency increased owing to additive effect. When its concentration increased to 5 wt%, conversion efficiency decreased due to its viscosity. As the concentration of methanol increased from 5 wt% to 10 wt%, conversion efficiency increased owing to additive effect. When its concentration increased to 15 wt%, conversion efficiency decreased due to $NaB(OCH_3)_4$ precipitate. Although conversion efficiency decreased about 1% when 3 wt% glycerol was added, $NaBO_2$ precipitation was prevented. Consequently, addition of 3 wt% glycerol to $NaBH_4$ solution improves stability of hydrogen generation system.

• 한국항공우주학회지
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• 제43권4호
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• pp.296-303
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• 2015

무인기 운용 환경을 고려하여 다양한 조성의 $NaBH_4$ 용액을 사용해 수소발생시스템의 성능 평가를 수행하였다. 먼저, 자발가수분해와 30분의 수소발생실험을 수행하였다. 수소의 손실, 안정한 수소 발생, $NaBO_2$의 석출, 전환 효율과 무인기의 운용을 고려하여 $NaBH_4$ 용액의 조성을 1 wt% NaOH + 25 wt% $NaBH_4$+74wt% $H_2O$로 결정하였다. 200 W급 연료전지 시스템을 위해 장시간 수소발생실험도 수행되었다. 비록 $NaBO_2$의 석출로 인해서 수소 발생률이 감소하였지만, 200 W 연료전지를 위한 수소를 3시간동안 발생(전환 효율: 87.4%)시켰다. 600 Wh의 에너지를 갖는 200 W급 연료전지 시스템의 에너지 밀도는 263 Wh/kg이었다. 기존 배터리 무인기에 비해 약 1.5배 이상의 체공 시간을 달성할 수 있다.