内生金属离子动态核极化用于金属有机框架中的NMR信号增强
Ilia B Moroz1, Yishay Feldman2, Raanan Carmieli2
1Department of Molecular Chemistry and Materials Science, Weizmann Institute of Science Rehovot 76100 Israel michal.leskes@weizmann.ac.il.
Chemical science
|December 22, 2023
概括
这项研究引入了一种使用加多离子被入金属有机框架 (MOF) 的新方法,以增强NMR信号,用于研究宿主-客人相互作用. 这种技术可以更清楚地了解用于催化和气体储存的MOF材料.
科学领域:
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
- 频谱学是一种光谱学.
背景情况:
- 用于催化和气体储存的金属有机框架 (MOF) 的合理设计需要了解宿主-客人相互作用.
- 固态核磁共振 (NMR) 谱学提供结构洞察力,但敏感性较低.
- 动态核极化 (DNP) 增强了NMR信号,但通常会通过要求孔隙浸来干扰宿主-客人研究.
研究的目的:
- 开发一种DNP-NMR方法,用于研究没有孔浸的MOF中的宿主-客人相互作用.
- 为了利用MOF结构中的Gd(iii) 离子作为有效的极化剂.
- 为了证明这种方法对MOF框架和客分子偏振的适用性.
主要方法:
- 兴奋剂LaBTB MOF与Gd(iii) 离子一起作为内置的极化源.
- 进行DNP-NMR实验,使用Gd(iii) -doped的LaBTB MOF,既空,又装有乙烯基醇.
- 调查诸如残留氧气和冷温度下的客/框架动态等挑战.
主要成果:
- 在使用Gd(iii) 离子的MOF链接器中实现了高达30倍的13C NMR信号增强.
- 在MOF毛孔内成功地极化了乙烯基醇客分子.
- 在MOF的DNP-NMR研究中,确定并解决了与氧气和动态相关的挑战.
结论:
- (iii) 兴奋剂提供了一种有效的,非侵入性的DNP-NMR方法来研究MOF宿主-客人相互作用.
- 这种方法可以对MOF及其客体进行详细的结构分析,这对于材料设计至关重要.
- 该方法可以适应其他与能源和可持续性研究相关的多孔材料.
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