一个具有4.7纳米孔的二维共价有机框架,并洞察其间层堆叠
Eric L Spitler1, Brian T Koo, Jennifer L Novotney
1Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York 14853, USA.
Journal of the American Chemical Society
|October 22, 2011
概括
研究人员合成了一种新的二维共价有机框架 (COF),具有创纪录的大孔,以实现高效的电荷传输. 先进的计算揭示了独特的层间堆叠,与典型的阴影结构不同.
科学领域:
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
- 有机化学 有机化学
背景情况:
- 二维分层共价有机框架 (2D COF) 提供有序的π电子系统,有利于激子和电荷传输.
- 它们的永久性多孔性允许多功能功能化.
- 开发具有增强结构性质的COF对于先进应用至关重要.
研究的目的:
- 为了合成一个具有迄今为止报告的最大孔径的二维COF.
- 用于制备微晶粉末和垂直导向薄膜形式的COF.
- 为了研究合成的COF的层间距和堆叠.
主要方法:
- 在2,3,6,7,10,11-Hexahydroxytriphenylene (HHTP) 和4,4'-diphenylbutadiynebis (酸) (DPB) 之间发生凝结反应.
- 在石墨烯/化基底上制备微晶粉末和薄膜.
- 分子动力学和密度函数理论 (DFT) 的计算.
主要成果:
- 成功合成了具有前所未有的大孔的2D COF.
- 描述COF既是一种高表面积粉末,又是一种垂直导向的薄膜.
- 计算分析表明,相邻层之间的水平偏移为1.7-1.8 Å,偏离了被遮蔽的AA堆叠.
结论:
- 合成的2DCOF具有异常大的毛孔,推进了COF设计.
- 在石墨烯上以薄膜形式准备材料,为设备集成开辟了道路.
- 发现的间层偏移为COF结构多态和包装提供了新的见解.
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