基于的金属有机框架中的过渡连锁及其对机械稳定性和吸附性能的影响
Lee Robison1,2, Xinyi Gong1,2, Austin M Evans1
1Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States.
Journal of the American Chemical Society
|January 12, 2021
概括
这项研究追踪了金属有机框架 (MOF) 从非透结构转变为透结构的过程. 相互透的MOF,STA-26,显示出更高的机械稳定性和气体捕获应用的潜力.
科学领域:
- 材料科学
- 化学学
- 纳米技术
背景情况:
- 在金属有机框架 (MOF) 中,子格子的相互穿透是常见的现象.
- 对于材料设计来说,了解非透性和透性MOF结构之间的过渡至关重要.
- 基于团的MOF提供了独特的结构可能性.
研究的目的:
- 研究基于团的MOF从非透性 (NU-1200) 到透性 (STA-26) 异构体的演变.
- 开发和展示一个模板方法来监测MOF的相互透.
- 评估两种MOF异构体的机械稳定性和气体捕获潜力.
主要方法:
- 使用孔度和X射线衍射间接观察相互透.
- 使用高分辨率传输电子显微镜直接观察相互透.
- 通过压缩现场X射线衍射,纳米缩和密度函数理论计算进行机械稳定性评估.
主要成果:
- 通过组合和直接成像技术的组合,成功监测了从NU-1200到STA-26的过渡连锁过程.
- 发现STA-26的机械稳定性明显高于NU-1200.
- 这项研究表明,这些MOF具有捕获气态n-hexane的潜力.
结论:
- 开发的方法提供了一个模板,用于监测MOF在散装和单颗粒水平上的相互透.
- 由于STA-26的增强机械稳定性,使其成为先进应用的有希望的候选材料.
- 这些MOF及其混合相具有捕获挥发性有机化合物和化学战剂模拟的潜力.
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