中距离的顺序结构控制孔的热稳定性,在地石的imidazolate框架
Rasmus Christensen1, Yossi Bokor Bleile2,3, Søren S Sørensen1
1Department of Chemistry and Bioscience, Aalborg University, Aalborg 9220, Denmark.
The journal of physical chemistry letters
|August 14, 2023
概括
金属有机框架 (MOF) 玻璃通过在液态状态下保持中等范围的顺序结构来保持多孔性. 这项研究表明,ZIF-76保持了更多的秩序,导致MOF眼镜的多孔性更高.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 物理 物理学 物理
背景情况:
- 金属有机框架 (MOF) 玻璃结合了传统玻璃和MOF的特性.
- 融灭通常会降低MOF玻璃的多孔性,其起源不清楚.
- 了解孔隙收缩对于开发功能性MOF眼镜至关重要.
研究的目的:
- 研究MOF玻璃在化过程中透性损失的结构基础.
- 分析泽奥利特化伊米达酸框架 (ZIF) 的化行为.
- 确定在玻璃状状态下保持多孔性的结构特征.
主要方法:
- 使用*ab initio*分子动力学 (MD) 模拟来建模ZIF融.
- 应用拓数据分析来解释MD模拟数据.
- 检查了短期和中期的结构变化.
主要成果:
- 所有三个研究的ZIF (ZIF-4,ZIF-62,ZIF-76) 在加热后都显示出类似的短距离顺序变化.
- 在中期顺序 (MRO) 的结构演变中观察到显著的差异.
- 与ZIF-4和ZIF-62相比,ZIF-76在液态状态中保留了更多的MRO.
结论:
- MOF玻璃保持多孔性的能力与在液态状态下保存MRO有关.
- 齐夫-76的优越的MRO保留力解释了其灭后更高的多孔性.
- 这些发现为设计具有增强孔隙性的MOF眼镜提供了洞察力.
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