Study of physicochemical and dielectric proprieties of dicationic ionic liquids: the effect of the nature of the cation



Abstract. In this paper a comparative study of three dicationic ionic liquids (DILs) is presented, these latter are characterized by sharing tetrafluoroborate [2BF4-] as anion and have three different structure piperidinium based cations [R1(CH2)nPPI2+]; namely: bis-methyl piperidinium propylidene [MPrPPI2+], bis-methyl piperidinium butylidene [MBPPI2+]and bis-ethyl piperidinium butylidene [EBPPI2+], their structures were characterized by using 1H, 13C, 19F-NMR and FT-IR techniques. In the frequency range [from 10-2 to 106 Hz] and over the temperature range from [212 to 248 K], real dielectric (ε’), imaginary dielectric (ε”), conductivity (σ) and complex electrical modulus (M*)-frequency (ω) relationships of these three ILs were investigated using dielectric spectroscopy and electric modulus formalism. In this context, the dielectric permittivity, conductivity and the activation energy values are observed to be increased respectively; on one hand, with the spacer length from [MPrPPI2+] to [MBPPI2+] and on the other hand, with the alkyl chain length attached to the cationic from [MBPPI2+] to [EBPPI2+] of the dicationic ionic liquids. Also, the results suggest that the effect of alkyl chain length is more important to the spacer length effect on the dielectric permittivity and conductivity proprieties. Finally, the activation energy is determined in order to understand the relaxation processes in our DILs.

Dicationic Ionic Liquids (DILs), Tetrafluoroborate, Dielectric Relaxation Spectroscopy (DRS), Conductivity

Published online 12/10/2016, 4 pages
Copyright © 2016 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA
Citation: B. HADDAD, E. BELARBI, T. MOUMENE, M. RAHMOUNI, D. VILLEMIN, ‘Study of physicochemical and dielectric proprieties of dicationic ionic liquids: the effect of the nature of the cation’, Materials Research Proceedings, Vol. 1, pp 9-12, 2016

The article was published as article 3 of the book Dielectric Materials and Applications

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