旋转的环作为客户依赖的开关在二维金属有机框架中的二维金属有机框架
Christopher R Murdock1, Nicholas W McNutt, David J Keffer
1Department of Chemistry, ‡Department of Chemical and Biomolecular Engineering, and §Department of Materials Science and Engineering, University of Tennessee , Knoxville, Tennessee 37996-1600, United States.
Journal of the American Chemical Society
|December 20, 2013
概括
具有可调节纳米管的新型金属有机框架表现出动态转换. 环旋转调整管子大小,由客分子和溶解控制,为框架监测提供了一种新方法.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 超分子化学 超分子化学
背景情况:
- 金属有机框架 (MOF) 是具有多种应用的晶体材料.
- 具有可调节孔隙性的异型MOF具有显著的研究兴趣.
- 了解MOF中的固态转换对于其实际使用至关重要.
研究的目的:
- 为了合成和描述新的2D金属有机框架与1D纳米管拓.
- 为了研究这些框架的固态转换,以应对溶解.
- 探索客分子包容和框架呼吸的机制.
主要方法:
- 合成 bis ((1,2,4-三) 铜 ((I) 框架.
- 单晶X射线衍射用于结构分析.
- 粉末X射线衍射 (PXRD) 和固态 (13C) 交叉极化神奇角度旋转 (CP-MAS) NMR用于监测转换.
- 计算模拟以了解能源动态.
主要成果:
- 2D金属有机框架的形成与化的1D纳米管拓.
- 观察了两个不同的固态转换:层膨胀/收缩和环旋转.
- 环旋转允许调节管子大小,显示出"门"效应.
- 固态 (13)C CP-MAS NMR直接监测旋和框架呼吸,性能优于PXRD.
结论:
- 合成的MOF表现出了显著的动态行为和可调节的多孔性.
- 环旋转是控制纳米管内客分子访问的关键机制.
- 固态 (13) C CP-MAS NMR是一种强大的工具,用于表征框架呼吸和溶解驱动的转换.
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