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A Highly Conductive RTMS; EMIF.2.3HF R. Hagiwara,
T. Tsuda, T. Hirashige, Y. Ito Graduate
School of Energy Science, Kyoto University Sakyo-ku,
Kyoto 606-8501, Japan Metathesis of
some alkylimidazolium salts such as 1-ethyl-3-methyl imidaz olium chloride
(EMICl) and anhydrous hydrogen fluoride (HF) at room temperat ure give
involatile liquid. The composition is expressed by an equation, EMI F.2.3HF [1]
from the result of elemental analysis, gravimetry, H and D-NMR. Vibrational
and NMR spectroscopies indicate that this liquid is ionic, and a 7:3 mixture of
two salts, EMI+[(HF)2F]- and EMI+[(HF)3F]- [2]. It is stable in air and
does not etch a Pyrex glass container at ambient conditions. It d oes not freeze
above -90_$B!#_(JC or lose HF below 100_$B!#_(JC. Irreversible decompositio n occurs in
inert atmosphere at around_$B!!_(J300 _$B!#_(JC. The viscosity of the liquid is 4.85 cP at
298 K, giving an ionic conductivity of 100 mScm-1 which is rem arkably high
compared with that found for other ionic liquids [3]. These fla t ion RTMS
exhibit extremely high conductivity [4]. We have recently succeed ed to
immobilize the salt in poly-2-hydroxyethyl methacryrate to make a high ly conductive
solid polymer electrolyte (19 mScm-1 at 303 K) [5]. Temperatur e dependence
of the viscosity and conductivity obeys a VTF equation. EMIF.2. 3HF gives a
wide electrochemical window of ~4 V, applications as an electrol yte being
envisaged to many fields in electrochemistry in addition to a reac tion solvent
in synthetic chemistry. REFERENCES 1. R.
Hagiwara, T. Hirashige, T. Tsuda, Y. Ito, J. Fluorine Chem., 99, 1 (1999). 2. R.
Hagiwara, T. Hirashige, T. Tsuda, and Y. Ito, submitted to Inorg. Chem... 3. R.
Hagiwara, and Y.Ito, J. Fluorine Chem., 105, 221(2000). 4. R.
Hagiwara, T. Tsuda, T. Hirashige, and Y. Ito, Proc. of 8th China-Japan Bilateral
Conference on Molten Salt Chemistry and Technology, (2000). 5. T. Tsuda,
R. Hagiwara, and Y. Ito, Proc. of 8th China-Japan Bilateral Con ference on
Molten Salt Chemistry and Technology, (2000). ********************************************** Prof. Rika
Hagiwara Department of
Fundamental Energy Science Graduate
School of Energy Science Kyoto
University Sakyo-ku,
Kyoto 606-8501 JPN TEL
+81-75-753-5822 FAX
+81-75-753-5906 ********************************************** |
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