在微孔金属有机框架中的广泛歇斯底里H2吸附 (1,4-二甲酸)
Hye Jin Choi1, Mircea Dincă, Jeffrey R Long
1Department of Chemistry, University of California, Berkeley, California 94720, USA.
Journal of the American Chemical Society
|June 3, 2008
概括
一个新的金属有机框架表现出灵活的结构和高表面积,显示出储存的潜力. 研究了其独特的吸附特性和H2扩散动态.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 纳米技术 纳米技术
背景情况:
- 金属有机框架 (MOF) 是多孔晶体材料,具有多种应用.
- 开发具有适合气体储存和分离的特性的MOF是一个活跃的研究领域.
研究的目的:
- 通过和一种新的联结体合成和描述一种新的金属有机框架.
- 研究合成的MOF的结构,热和气体吸附特性.
- 探索这种MOF在储存方面的潜力,并研究H2扩散动态.
主要方法:
- 通过溶热反应合成金属有机框架Co(BDP).2DEF.H2O.
- 用X射线衍射 (XRD) 和粉末XRD进行结构分析.
- 热重力测量分析 (TGA) 用于热稳定性和溶解研究.
- 和高压吸附等热体以确定表面积和气体吸收.
- 用于H2扩散分析的可变温度动力学测量.
主要成果:
- 合成的MOF,Co(BDP).2DEF.H2O,形成了一个3D框架,具有10x10 Å通道.
- 该框架表现出高的热稳定性和灵活性,在溶解/溶解时可逆转换.
- 吸附揭示了高表面积 (2670 m2/g) 和一个不寻常的五步吸附过程.
- 高压H2吸附显示出歇斯底里吸收/释放,其容量在50K时为5.5%的重量%.
- 研究了MOF内的H2扩散,产生0.62kJ/mol的能量屏障.
结论:
- 小说MOF表现出灵活的框架和显著的孔隙性,使其成为储存的有希望的候选人.
- 观察到的H2吸附行为表明,在气体储存中可能存在动力捕获机制.
- 这项研究提供了首次对MOF内的H2扩散动力学的研究,为客分子动力学提供了洞察力.
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