The surface properties of a series of 1-alkyl-3-methylimidazolium (AMIM)-based ionic liquids (ILs) were characterized using an inverse gas chromatography technique at temperatures from 343.15 to 373.15 K. Nine polar and nonpolar probe solvents were used to investigate the surface properties, which included the Lewis acid–base constants, adsorption free energy, enthalpy adsorption, and dispersive component of the surface free energy (r_s^d). Furthermore, the effects of the alkyl chain length of the cation and the different anions on the surface properties were also studied. The results indicated that all of the investigated ILs were Lewis amphoteric material with low r_s^d values. When the anion was kept as [PF₆]⁻, r_s^d of the series of AMIM-based ILs linearly decreased as the alkyl chain length was increased in the imidazolium cation, and the basicity also decreased as the alkyl chain length was increased.

中文翻译：

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反相气相色谱法表征一系列基于1-烷基-3-甲基咪唑鎓的离子液体

使用反相气相色谱技术在343.15至373.15 K的温度下表征了一系列基于1-烷基-3-甲基咪唑鎓（AMIM）的离子液体（IL）的表面性质。使用九种极性和非极性探针溶剂进行研究表面性质，包括路易斯酸碱常数，吸附自由能，焓吸附和表面自由能的分散成分（r _s ^d）。此外，还研究了阳离子和不同阴离子的烷基链长对表面性能的影响。结果表明，所有研究的ILs都是具有低r _s ^d值的路易斯两性材料。当阴离子保持为[PF ₆ ]时^-，随着咪唑鎓阳离子中烷基链长度的增加，一系列基于AMIM的IL的r _s ^d线性降低，并且随着烷基链长度的增加，碱度也降低。