Jaegers Nicholas R, Hu Wenda, Wang Yong, Hu Jian Zhi
Pacific Northwest National Laboratory.
Washington State University.
J Vis Exp. 2020 Oct 9(164). doi: 10.3791/61794.
Nuclear magnetic resonance (NMR) spectroscopy represents an important technique to understand the structure and bonding environments of molecules. There exists a drive to characterize materials under conditions relevant to the chemical process of interest. To address this, in situ high-temperature, high-pressure MAS NMR methods have been developed to enable the observation of chemical interactions over a range of pressures (vacuum to several hundred bar) and temperatures (well below 0 °C to 250 °C). Further, the chemical identity of the samples can be comprised of solids, liquids, and gases or mixtures of the three. The method incorporates all-zirconia NMR rotors (sample holder for MAS NMR) which can be sealed using a threaded cap to compress an O-ring. This rotor exhibits great chemical resistance, temperature compatibility, low NMR background, and can withstand high pressures. These combined factors enable it to be utilized in a wide range of system combinations, which in turn permit its use in diverse fields as carbon sequestration, catalysis, material science, geochemistry, and biology. The flexibility of this technique makes it an attractive option for scientists from numerous disciplines.
核磁共振(NMR)光谱学是理解分子结构和键合环境的一项重要技术。人们一直致力于在与感兴趣的化学过程相关的条件下对材料进行表征。为了实现这一点,已经开发了原位高温、高压魔角旋转核磁共振方法,以便能够在一系列压力(真空至几百巴)和温度(远低于0°C至250°C)下观察化学相互作用。此外,样品的化学性质可以由固体、液体和气体或三者的混合物组成。该方法采用全氧化锆核磁共振转子(用于魔角旋转核磁共振的样品管),可以使用螺纹盖密封以压缩O形环。这种转子具有很强的化学抗性、温度兼容性、低核磁共振本底,并且能够承受高压。这些综合因素使其能够应用于广泛的系统组合中,进而允许其在碳封存、催化、材料科学、地球化学和生物学等不同领域中使用。这项技术的灵活性使其成为众多学科科学家的一个有吸引力的选择。