X-ray photoelectron spectroscopy of morpholinium ionic liquids: impact of a long alkyl side substituent on the cation-anion interactions.
X-ray photoelectron spectroscopy of morpholinium ionic liquids: impact of a long alkyl side substituent on the cation-anion interactions.
复制标题
吗啉鎓离子液体的 X 射线光电子能谱：长烷基侧取代基对阳离子-阴离子相互作用的影响。
DOI：
10.1039/d2cp03674f
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Men S
中科院分区：
文献类型：
--
作者：
Men S
本文采用X射线光电子能谱法对9种吗啉离子液体进行了分析，这些离子液体因其毒性低、可回收性好而在绿色化学中具有重要的应用价值。考察了烷基链长对脂肪族C1 s结合能的影响以及阴离子碱度对阳离子N1s和O 1 s结合能的影响。结果表明，通过改变阴离子的碱性，氧中心的电子环境发生了更为显著的变化。长烷基侧取代基对阳离子-阴离子相互作用的影响也进行了讨论。据观察，有一个强烈的电荷屏蔽效应的烷基侧链的情况下，辛基和十二烷基取代基，这是反映在减少Br 3d 5/2结合能。
In this study, X-ray photoelectron spectroscopy is used to analyse nine morpholinium ionic liquids, which are of great interest in green chemistry because of their low toxicity and high recyclability. The effect of the alkyl chain length on the aliphatic C 1s binding energy and the impact of the anion basicity on the cationic N 1s and O 1s binding energies are investigated. It is concluded that by changing the basicity of the anion, there is a more notable change in the electronic environment of the oxygen centre. The impact of a long alkyl side substituent on the cation–anion interactions is also discussed. It is observed that there is an intense charge shielding effect of the alkyl side chain in the cases of octyl and dodecyl substituents, which is reflected in the reduced Br 3d5/2 binding energy.