在多孔的有机晶体中构建一个上层结构
Peng Li1, Nicolaas A Vermeulen1, Christos D Malliakas1
1Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
概括
化学家们使用简单的组件制造出一种复杂的基金属有机框架 (MOF). 这一突破产生了有史以来最大的单元细胞和最低密度的MOF, 展示了复杂的结构复杂性.
科学领域:
- 材料科学
- 化学学
- 纳米技术
背景情况:
- 从基本的构件构建复杂的化学结构是一个重大的科学挑战.
- 金属有机框架 (MOF) 具有可调节的特性,但仍然难以实现高结构复杂性.
研究的目的:
- 报告一个结构复杂的,以为基础的金属有机框架 (MOF).
- 描述这种新型MOF的前所未有的结构复杂性和由此产生的特性.
主要方法:
- 使用简单的起始组件进行自下而上的合成.
- 结晶学分析以确定单元尺寸和原子排列.
- 孔隙性和密度的表征
主要成果:
- 一种以为基础的MOF,具有173.3安格斯特罗姆的立方单元,这是所有非生物材料中最大的.
- 该结构具有10个独特的节点和7个独特的三碳酸连接体,组织成复杂的四面体和钻石拓.
- 形成巨大的腔 (5.0 nm和6.2 nm内部直径) 导致迄今为止密度最低的MOF.
结论:
- 这一成功的合成证明了MOF的复杂性.
- 这项工作扩大了设计具有定制性质的先进多孔材料的可能性.
- 由此产生的超低密度MOF在需要高表面积和低质量的领域具有潜在的应用.
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