New & Renewable Energy (신재생에너지)

Korean Society for New and Renewable Energy (한국신·재생에너지학회)
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Ammonia Decomposition Over Tantalum Carbides of Hydrogen Fuel Cell

수소연료전지용 탄탈륨 탄화물에 대한 암모니아 분해반응

  • Choi, Jeong-Gil (Department of chemical engineering and Nano-bio technology, Hannam University)
  • 최정길 (한남대학교 나노생명화학공학과)
  • Received : 2013.01.28
  • Accepted : 2013.02.26
  • Published : 2013.03.25
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Abstract

Tantalum carbide crystallites which is to be used for $H_2$ fuel cell has been synthesized via a temperature-programmed reduction of $Ta_2O_5$ with pure $CH_4$. The resultant Ta carbide crystallites prepared using two different heating rates and space velocity exhibit the different surface areas. The $O_2$ uptake has a linear relation with surface area, corresponding to an oxygen capacity of $1.36{\times}10^{13}\;O\;cm^{-2}$. Tantalum carbide crystallites are very active for hydrogen production form ammonia decomposition reaction. Tantalum carbides are as much as two orders of magnitude more active than Pt/C catalyst (Engelhard). The highest activity has been observed at a ratio of $C_1/Ta^{{\delta}+}=0.85$, suggesting the presence of electron transfer between metals and carbon in metal carbides.

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References

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