在金属-有机框架MFM-133 ((M) 中异常和可调节的负线性可压缩性 (M = Zr, Hf)
Yong Yan1, Alice E O'Connor2, Gopikkaa Kanthasamy2
1School of Chemistry , University of Manchester , Oxford Road , Manchester M13 9PL , United Kingdom.
Journal of the American Chemical Society
|February 3, 2018
概括
像MFM-133这样的金属有机框架 (MOF) 在压力下表现出负线性压缩性 (NLC). 研究人员通过在框架内改变金属离子 (Zr,Hf) 来调整NLC属性.
科学领域:
- 材料科学
- 晶体学
- 化学学
背景情况:
- 金属有机框架 (MOF) 是具有多种应用的晶体多孔材料.
- 负线性压缩性 (NLC) 是一种罕见的现象,在水静压下,材料向一个方向收缩.
- 了解MOF中的NLC对于设计具有定制机械反应的材料至关重要.
研究的目的:
- 研究同结构MOF,MFM-133 (Zr) 和MFM-133 (Hf) 的高压结构行为.
- 确认和阐明这些材料的负线性可压缩性 (NLC) 的机制.
- 通过改变MOF中的金属成分来证明NLC的调性.
主要方法:
- 使用高压单晶X射线衍射分析了晶体结构.
- 同结构的MOF,MFM-133 (Zr) 和MFM-133 (Hf) 合成了TCHB连接体.
- 分析了压缩下的结构变化,以了解NLC机制.
主要成果:
- MFM-133 ((Zr)) 和MFM-133 ((Hf)) 在c轴上均表现出负线性压缩性 (NLC).
- 一个3D葡萄酒架机制驱动NLC,导致压力下的八面体变形.
- 与MFM-133 ((Zr) 相比,MFM-133 ((Hf)) 的NLC程度更高.
结论:
- 在同结构MOF中,通过改变金属离子 (Zr与Hf) 可以有效调整NLC属性.
- 这种调整在不改变框架的拓或整体结构的情况下实现.
- 这项研究为设计具有可控制机械性能的MOF提供了一种新的策略.
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