连接金属有机框架材料中的选择性气体吸收和旋转动力学
William J F Trenholme1,2, Daniil I Kolokolov3,4, Michelle Bound2
1School of Chemistry, University of Manchester, Oxford Road, Manchester M13 9PL, U.K.
Journal of the American Chemical Society
|February 24, 2021
概括
这项研究介绍了MFM-160a,一种具有特殊的二氧化碳 (CO2) 吸收和碳化合物的选择性分离的金属有机框架 (MOF) 材料. 它的独特特性与气体结合所影响的动态连接器旋转有关.
科学领域:
- 材料科学
- 化学学
- 化学工程
背景情况:
- 金属有机框架 (MOF) 是可调节气体储存和分离的多孔材料.
- 开发具有高选择性和工业相关气体容量的MOF仍然是一个关键挑战.
- 了解MOF链接器的动态行为对于优化其性能至关重要.
研究的目的:
- 合成和描述一种新的 (3,24) 连接的MOF,MFM-160a.
- 评估MFM-160a对碳化合物的二氧化碳吸收和选择性分离能力.
- 研究MOF连接器的动态行为及其与气体吸附的关系.
主要方法:
- 合成和溶解MOF材料MFM-160a.
- 对CO2,C2H2,C2H4和CH4的高压气体吸附测量
- 固态2H核磁共振光谱用于研究链接器动态.
- 密度函数理论 (DFT) 计算以建模气体链接器相互作用.
主要成果:
- MFM-160a具有较高的二氧化碳吸收率 (在20 bar时为110%) 和C2碳化合物与CH4的选择性分离 (例如,C2H2:CH4的选择性为79:1).
- 在MOF链接器中观察到基的超低屏障旋转,旋转速度明显低于典型的固态材料.
- 发现气体吸附 (CO2,C2H2) 增加了链接器的旋转速率,这归因于分子内键的减弱.
结论:
- 在二氧化碳捕获和碳化合物分离方面,MFM-160a表现出有前途的性能.
- MFM-160a的动态连接器旋转是影响其气体吸附性能的关键因素.
- 观察到的链接器动态中的气体诱导变化为MOF-气体相互作用和设计原则提供了洞察力.
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