通过固态NMR和计算机建模研究的氨基功能化中化学吸收CO2的结构
Luís Mafra1, Tomaž Čendak1, Sarah Schneider1
1CICECO - Aveiro Institute of Materials, Department of Chemistry, University of Aveiro , Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
Journal of the American Chemical Society
|December 14, 2016
概括
这项研究使用先进的NMR揭示了二氧化碳 (CO2) 如何与氨基功能化材料结合的新细节. 这些发现澄清了二氧化碳吸附结构,这对于开发高效的碳捕获技术至关重要.
科学领域:
- 材料科学
- 化学学
- 光谱学
背景情况:
- 像SBA-15这样的氨基功能化材料对二氧化碳捕获具有前景.
- 了解二氧化碳的精确结构对于优化捕获效率至关重要.
研究的目的:
- 通过使用先进的NMR技术,阐明用氨基功能化SBA-15形成的CO2添加物的结构细节.
- 确定和描述不同化学吸收的二氧化碳物种及其相互作用.
主要方法:
- 使用13C标记的CO2进行二维 (2D) 固态核磁共振 (SSNMR) 实验.
- 基于1H的SSNMR研究,包括1D1H和2D1H-X异质核相关性 (HETCOR) 实验.
- 密度函数理论 (DFT) 计算以帮助光谱分配和结构验证.
主要成果:
- 确定了三种不同化学吸收的二氧化碳物种,碳烯共振在153,160和164ppm.
- 发现了一种新型的CO2物种,
- 证实所有化学吸收的二氧化碳物种与表面醇或胺形成键 (HBs),其中一些具有非常强的HBs.
- 排除了碳酸盐或二碳酸盐物种的形成.
- DFT计算支持1H/13C NMR信号的分配,并验证了与碳酸形成一致的HB安排.
结论:
- 这项研究为氨基功能化SBA-15的二氧化碳化学吸收提供了前所未有的结构见解.
- 核磁共振光谱被证明是一种强大的工具,用于区分自由和与结合的功能组.
- 这些发现有助于更好地理解与表面氨基的二氧化碳结合机制,这与压力摆动吸附过程有关.
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