H2部分压力对含的多组件不稳定储存系统的反应进展和可逆性的影响
Tobias E C Price1, David M Grant, David Weston
1Energy and Sustainability Research Division, Engineering Faculty, The University of Nottingham, University Park, Nottingham, NG7 2RD, UK.
Journal of the American Chemical Society
|July 16, 2011
概括
的部分压力显著影响化:化分解. 低压使合金在冷却时形成LiH和Mg,影响可逆性和释放的测量.
科学领域:
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
- 储存气的储存方式
背景情况:
- 众所周知,LiBH(4):MgH(2) 系统的分解途径在真空和压下有所不同.
- 之前的研究没有研究这种多元组件化物系统对低部分压的敏感性.
研究的目的:
- 研究的低部分压力对LiBH(4):MgH(2) 系统分解的影响.
- 了解真空条件对反应产品和可逆性的影响.
主要方法:
- 在现场粉末中子 difraktion (使用deuterides) 和X射线 difraktion.
- 通过使用不同的真空系统来控制的部分压力变化.
主要成果:
- 所有样品分解成Li-Mg合金,不论真空系统或石化计.
- 在冷却后,这些合金表现出相位不稳定性,并反应形成LiH和Mg,除了在最高效率真空条件下 (最低基压).
- 在现场实验中产生的明显的量受到动态真空条件的影响.
结论:
- LiBH ((4):MgH ((2) 的分解和随后的产品稳定性对低的部分压力敏感.
- 不一致的真空条件可能导致在多元组分化物研究中无法重现的结果.
- 在丰富的样本上形成被动化化物层阻碍了化,这解释了报告的可逆性差异.
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