金属有机框架UIO-66中的不寻常且高度可调节的缺失连接器缺陷及其对气体吸附的重要影响
Hui Wu1, Yong Shen Chua, Vaiva Krungleviciute
1NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-6102, United States.
Journal of the American Chemical Society
|July 2, 2013
概括
真正的UiO-66金属有机框架含有显著的缺失链接器缺陷,这增加了多孔性和气体吸附. 调整这些缺陷并利用基组可以提高性能,特别是在二氧化碳捕获方面.
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:
- UiO-66是一种具有高度连接结构的稳定金属有机框架 (MOF).
- 无缺陷的UiO-66具有理论上的多孔性和表面积值.
- 常见的多孔MOF通常缺乏在UiO-66.6中观察到的稳定性.
研究的目的:
- 为了研究真正的UiO-66材料中的结构缺陷.
- 了解缺失链接器缺陷对孔隙性和气体吸附性的影响.
- 探索调整缺陷和增强UiO-66属性的方法.
主要方法:
- 高分辨率的中子粉衍射用于识别结构缺陷.
- 乙酸调节器度和合成时间的系统变化.
- 气体吸附测量 (孔径,表面积,二氧化碳吸附).
- 支持实验发现的第一原则计算.
主要成果:
- 直接证据显示,UiO-66中存在显著的缺失链接器缺陷 (∼10%),从而降低了框架连接.
- 可调节的连接器空缺导致透度 (高达1.0cm3/g) 和表面积 (高达1600m2/g) 显著增加.
- 在氧化UIO-66上增强了气体吸附,特别是对CO2的吸附,与脱氧化形式相比.
结论:
- 缺失链接器缺陷是UIO-66固有的,对于其增强的特性至关重要.
- 缺陷工程提供了一条途径,可以显著提高MOF在气体储存和分离方面的性能.
- 氧化UiO-66表现出优异的气体吸附,突出显示了表面功能化的重要性.
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