短线性基的复杂吸附在柔性金属有机框架MIL-53 (Fe) 中
P L Llewellyn1, P Horcajada, G Maurin
1Laboratoire Chimie Provence, Université Aix-Marseille I-CNRS, UMR 6264, Centre de Saint Jérôme, 13397 Marseille, France. philip.llewellyn@univ-provence.fr
Journal of the American Chemical Society
|August 25, 2009
概括
铁MIL-53金属有机框架表现出复杂的吸附行为与短基因由于多孔开口. 这项研究揭示了它在气体吸收过程中的独特结构转变.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 像MIL-53这样的灵活的金属有机框架 (MOF) 在客分子吸附时表现出结构转变.
- 之前对MIL-53 ((Al) 和MIL-53 ((Cr) 的研究显示了不同的吸附行为.
- 铁的类似物,MIL-53 (Fe),由于其灵活的性质,是一个独特的案例.
研究的目的:
- 描述MIL-53 ((Fe) 与短线性基的异常吸附行为.
- 在吸附过程中研究MIL-53 ((Fe) 的结构变化.
- 为了阐明孔隙结构和吸附特性之间的关系.
主要方法:
- 结合了实验技术和计算建模.
- 气体吸附异热的测量. 气体吸附异热的测量.
- 在现场X射线粉碎衍射 (XRD).
- 分子模拟. 分子模拟.
主要成果:
- 对于短基,MIL-53 (Fe) 呈现出复杂的,多步骤的吸附同热体.
- 吸附步骤发生在依赖基的压力下.
- 在吸附过程中,确定了四种不同的孔隙开口大小.
- 在现场XRD和模拟证实了动态结构变化.
结论:
- 复杂的MIL-53 ((Fe) 吸附是由多个离散的孔隙开口驱动的.
- MIL-53 ((Fe) 具有独特的结构灵活性,与其Al和Cr对应物不同.
- 了解这些结构动态对于设计用于气体分离和储存的MOF至关重要.
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