The Effect of the Anion Fraction on the Physicochemical Properties of EMIm(HF)nF (n = 1.0−2.6)

• Published in: The journal of physical chemistry. B Vol. 109; no. 12; pp. 5445 - 5449
• Main Authors: HAGIWARA, Rika, NAKAMORI, Yoji, MATSUMOTO, Kazuhiko, ITO, Yasuhiko
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 31.03.2005
• ISSN: 1520-6106; 1520-5207
• DOI: 10.1021/jp047006l

A series of molten salts EMIm(HF)nF's with different n values has been synthesized by the reaction of EMImHF(2) and anhydrous hydrogen fluoride. The salts contain EMIm cation and some oligomeric fluorohydrogenate anions, (HF)nF-, of which the fraction changes with the change of n. A phase diagram of EMIm(HF)nF's (n = 1.0-2.6) has been constructed which suggests the presence of the stoichiometric compounds, EMIm(HF)1.5F and EMIm(HF)2F, in this range. Compared to the EMIm(HF)2.3F previously reported, EMIm(HF)nF's (n = 1.8-2.0) possess wider liquid temperature ranges because of their similar melting points and superior thermal stabilities at elevated temperatures. The electrochemical windows of EMIm(HF)nF's (n = 1.0-2.6) falls in the range of 2.9-3.4 V. The conductivity of EMIm(HF)nF's (n = 1.0-2.6) increases with the increase of n.