多孔分子晶体由宏环协调超分子组成
Irene Bassanetti1, Angiolina Comotti, Piero Sozzani
1Dipartimento di Chimica, Università degli Studi di Parma , viale delle Scienze 17/a, 43124 Parma, Italy.
Journal of the American Chemical Society
|September 25, 2014
概括
这项研究表明,银离子与特定连接体和反离子的协调如何创建多孔立方结构. 这些材料选择性地吸附CO2和N2O气体,通过连接物修饰可调节的多孔性.
科学领域:
- 超分子化学 超分子化学
- 协调化学 协调化学
- 材料科学 材料科学 材料科学
背景情况:
- 设计功能性多孔材料对于气体储存和分离等应用至关重要.
- 超分子自我组装为构建具有可调节性质的复杂架构提供了一条多功能途径.
研究的目的:
- 通过使用银离子,功能化连接体和特定的对抗离子,研究独特的超分子异构体 (协调聚合物和宏循环) 的形成.
- 描述由此产生的立方体结构,并评估它们的永久微孔性和气体吸附选择性.
主要方法:
- 合成了五种乙烯功能化双 (Pirazolyl) 甲联体.
- 与银离子 (Ag(+)) 和反离子 (triflate,CF3SO3(-),和六酸,PF6(-) 的配合体的协调.
- 使用X射线衍射和气体吸附异热体进行结构性表征.
- 固态NMR光谱学用于研究客分子扩散.
主要成果:
- 形成了两个不同的超分子异构体:带有CF3SO3的状协调聚合物链和PF6的六极分子宏循环.
- 六米宏循环自组装成具有永久微孔性的立方结构,表现出CO2和N2O对CH4和N2的选择性吸附.
- 连接体功能调节了微孔性,固态NMR证实了客人可以进入空洞.
结论:
- 谨慎选择金属离子,连接体和反离子,使复杂的超分子结构的合理设计成为可能.
- 合成的立方材料显示出选择性气体分离应用的潜力.
- 连接物修饰提供了一种策略来调整这些多孔协调材料的孔径和吸附性质.
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