一个共价有机框架的单晶结构
Yue-Biao Zhang1, Jie Su, Hiroyasu Furukawa
1Department of Chemistry, University of California , and Materials Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.
Journal of the American Chemical Society
|October 23, 2013
概括
研究人员使用先进的电子衍射确定了新的共价有机框架 (COF),COF-320的晶体结构. 这种高度多孔的材料显示出显著的甲吸收,推进了COF化学.
科学领域:
- 材料科学 材料科学 材料科学
- 化学 化学 化学
- 晶体学 晶体学是指结晶学.
背景情况:
- 聚合有机框架 (COF) 是具有可调节结构的晶体多孔聚合物.
- 确定COF中精确的原子排列对于理解它们的特性和应用至关重要.
- 单晶衍射方法对于精确的结构确定是理想的,但对于COF材料来说可能具有挑战性.
研究的目的:
- 为了确定一种新的共价有机框架的晶体结构,COF-320.
- 描述COF-320的多孔性和气体吸收特性.
- 为了证明单晶3D电子衍射对COF结构阐明的实用性.
主要方法:
- 通过对四甲和4,4'-二二甲的伊米因凝结合成COF-320.
- 单晶3D电子衍射使用旋转电子衍射 (RED) 方法进行数据收集.
- 气体吸附分析以确定表面积和甲吸收能力.
主要成果:
- 成功确定了COF-320的晶体结构,揭示了9倍交织的钻石网.
- COF-320具有永久的多孔性,Langmuir的高表面积为2400 m2 / g.
- 在25°C和80 bar时,COF-320显示了显著的甲吸收率为15.0 wt % (176 cm(3) / cm(3)).
结论:
- 使用单晶旋转电子衍射精确确定了COF-320的结构.
- COF-320是一种高度多孔的材料,具有出色的甲储存能力.
- 这项工作代表了对共价有机框架的结构性表征和发展的重大进展.
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