A highly conductive room temperature molten fluoride: EMIF center dot 2.3HF

Reaction of 1-ethyl-3-methylimidazolium chloride (EMICl) and anhydrous hydrogen fluoride gives a nonvolatile, room temperature molten salt, EMIF .2.3HF. The elemental analysis, vibrational, and nuclear magnetic resonance spectroscopy suggests the presence of oligomeric anions, (HF)(n)F- in the salt. The liquid is stable in air and able to be handled in a Pyrex glass vessel. The specific conductivity is 100 mS cm(-1) at 298 K, which is extremely high compared with other salts of this kind. The high conductivity is realized by its low viscosity (4.85 cP at 298 K). The liquid temperature ranges from 180 to 350 K, and electrochemical window is about 3.2 V when a vitreous carbon is used for the electrode material. (C) 2001 The Electrochemical Society.