Belieres Jean-Philippe, Angell C Austen
Department of Chemistry, Arizona State University, Tempe Arizona 85287-1604, USA.
J Phys Chem B. 2007 May 10;111(18):4926-37. doi: 10.1021/jp067589u. Epub 2007 Apr 7.
We give a perspective on the relations between inorganic and organic cation ionic liquids (ILs), including members with melting points that overlap around the borderline 100 degrees C. We then present data on the synthesis and properties (melting, boiling, glass temperatures, etc.) of a large number of an intermediate group of liquids that cover the ground between equimolar molecular mixtures and ILs, depending on the energetics of transfer of a proton from one member of the pair to the other. These proton-transfer ILs have interesting properties, including the ability to serve as electrolytes in solvent-free fuel cell systems. We provide a basis for assessing their relation to aprotic ILs by means of a Gurney-type proton-transfer free energy level diagram, with approximate values of the energy levels based on free energy of formation and pK(a) data. The energy level scheme allows us to verify the relation between solvent-free acidic and basic electrolytes, and the familiar aqueous variety, and to identify neutral protic electrolytes that are unavailable in the case of aqueous systems.
我们阐述了无机和有机阳离子离子液体（ILs）之间的关系，包括熔点在100℃左右临界值附近重叠的成员。然后我们展示了大量中间类液体的合成及性质（熔点、沸点、玻璃化温度等）数据，这些液体介于等摩尔分子混合物和离子液体之间，这取决于质子从一对中的一个成员转移到另一个成员的能量学。这些质子转移离子液体具有有趣的性质，包括能够在无溶剂燃料电池系统中用作电解质。我们通过一个古内型质子转移自由能级图为评估它们与非质子离子液体的关系提供了基础，该图的能级近似值基于生成自由能和pK(a)数据。能级方案使我们能够验证无溶剂酸性和碱性电解质与常见水性电解质之间的关系，并识别出水性系统中不存在的中性质子电解质。
