在纳米孔状材料中产生歇斯底里吸附的微观理论
Joongoo Kang1, Su-Huai Wei, Yong-Hyun Kim
1National Renewable Energy Laboratory, Golden, Colorado 80401, USA.
Journal of the American Chemical Society
|January 22, 2010
概括
研究人员解释了纳米多孔金属有机框架 (MOF) 中增强的吸附歇斯底里. 由于在小孔中通过扩散控制的过程,歇斯底里斯随着温度的增加而显著增加.
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.
- 物理化学 物理化学
背景情况:
- 在纳米孔中吸附气体对于催化和气体储存至关重要.
- 在纳米孔金属有机框架 (MOFs) 中观察到 (H2) 吸附中的歇斯底里.
研究的目的:
- 介绍一个微观理论增强H2吸附歇斯底里斯在MOFs.
- 调查扩散和温度对MOF中H2吸附的作用.
主要方法:
- 第一原则计算.第一原则计算.
- 模拟吸附/脱附等热体.模拟吸附/脱附等热体.
- 暂时吸附动态的分析.
主要成果:
- 开发了一种用于增强H2吸附歇斯底里在MOF Co{1,4-二酸) [Co{BDP]) 中的显微理论.
- 在小毛孔通道中激活的H2扩散被确定为主导平衡过程,导致歇斯底里.
- 一个小的温度升高大大提高了hysteresis压力宽度和吸附/脱附压力.
结论:
- 在MOF中歇斯底里H2吸附是扩散控制小孔系统的内在特征.
- 这些系统中气体吸附对温度变化的敏感性可以通过气体储热力学来解释.
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