具有nbo拓的立方3D共价有机框架
Xue Wang1,2, Mounib Bahri3, Zhiwei Fu2
1Leverhulme Research Centre for Functional Materials Design, University of Liverpool, Liverpool, L7 3NY, U.K.
Journal of the American Chemical Society
|September 13, 2021
概括
研究人员使用正方形平面 (II) 氨酸单元和螺旋酸连接合成了一种新型多孔的三维共价有机框架 (3D COF). 这种新材料SPB-COF-DBA具有高晶度和显著的表面积.
科学领域:
- 材料科学
- 化学学
- 纳米技术
背景情况:
- 三维 (3D) 共价有机框架 (COF) 是各种领域的关键材料.
- 它们的合成通常依赖于高连接性的构件或对结构对齐的精确控制.
- 实现特定的网络拓,如nbo拓,仍然是一个综合性挑战.
研究的目的:
- 用nbo拓构建3DCOF的新合成策略.
- 使用正方形平面 (PcCo) 单元和四面体螺旋酸盐 (SPB) 连接来控制框架组装.
- 描述产生的COF的结构,晶体和多孔性质.
主要方法:
- 使用可控对齐策略使用PcCo单元和SPB链接.
- 使用SPB连接在PcCo单元之间强制执行90°二面角,指导nbo拓的形成.
- 使用粉末X射线衍射 (PXRD) 和高分辨率传输电子显微镜 (HR-TEM) 进行合成材料 (SPB-COF-DBA) 的表征.
主要成果:
- 通过非透的nbo拓成功合成了多孔3DCOF,SPB-COF-DBA.
- SPB-COF-DBA具有高晶度和远程顺序,通过PXRD的11个分辨率峰值得到证实.
- 通过HR-TEM成像验证了良好的晶格.
- 该材料具有立方孔和永久透性,BET表面积为1726 m2g-1.
结论:
- 使用特定构件的控制对齐策略对于构建复杂的3DCOF拓是有效的.
- SPB-COF-DBA是一种新型,高度结晶,多孔材料,在需要高表面积材料的领域具有潜在的应用.
- 这项研究证明了PCO单元成功地集成到一个具有可界定孔隙性的强大3D框架中.
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