State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China.
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China.
Solid State Nucl Magn Reson. 2018 Apr-May;90:1-6. doi: 10.1016/j.ssnmr.2017.12.004. Epub 2017 Dec 29.
Solid-state NMR was utilized to explore the host-guest interaction between adsorbate and adsorbent at atomic level to understand the separation mechanism of styrene (St) and ethylbenzene (EB) in MIL-53(Al). C-Al double-resonance NMR experiments revealed that the host-guest interaction between St and MIL-53 was much stronger than that of EB adsorption. In addition, C DIPSHIFT experiments suggested that the adsorbed St was less mobile than EB confined inside the MIL-53 pore. Furthermore, the host-guest interaction model between St, EB and MIL-53 was established on the basis of the spatial proximities information extracted from 2D H-H homo-nuclear correlation NMR experiments. According to the experimental observation from solid-state NMR, it was found that the presence of π-π interaction between St and MIL-53 resulted in the stronger host-guest interaction and less mobility of St. This work provides direct experimental evidence for understanding the separation mechanism of St and EB using MIL-53 as an adsorbent.
采用固态 NMR 技术在原子水平上研究了吸附质与吸附剂之间的主客体相互作用，以了解苯乙烯（St）和乙苯（EB）在 MIL-53(Al) 中的分离机理。C-Al 双共振 NMR 实验表明，St 与 MIL-53 之间的主客体相互作用比 EB 吸附强得多。此外，C DIPSHIFT 实验表明，吸附的 St 比限制在 MIL-53 孔内的 EB 移动性差。此外，根据 2D H-H 同核相关 NMR 实验提取的空间邻近信息，建立了 St、EB 和 MIL-53 之间的主客体相互作用模型。根据固态 NMR 的实验观察，发现 St 和 MIL-53 之间存在 π-π 相互作用，导致更强的主客体相互作用和 St 的流动性降低。这项工作为使用 MIL-53 作为吸附剂理解 St 和 EB 的分离机制提供了直接的实验证据。
