Influence of the anion on the electrical conductivity and glass formation of 1-butyl-3-methylimidazolium ionic liquids

Leys, Jan; Rajesh, R.; Menon, Preethy; Glorieux, Christ; Longuemart, S.; Nockemann, Peter; Pellens, Michael; Binnemans, Koen

doi:10.1063/1.3455892

Cited by 67 publications

(58 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Both, the main relaxation time and the dc conductivity reveal the typical non-Arrhenius temperature dependence known from glass forming systems. Such behavior was reported for many ionic liquids 25,32,34,50,53,55,56,57,58,59,60,61 . Fits (solid lines) with the empirical Vogel-Fulcher-Tammann (VFT) law 62,63,64,65 ,…”

Section: Dielectric Spectroscopysupporting

confidence: 69%

Dielectric study on mixtures of ionic liquids

Thoms

Sippel

Reuter

et al. 2017

Sci Rep

View full text Add to dashboard Cite

Ionic liquids are promising candidates for electrolytes in energy-storage systems. We demonstrate that mixing two ionic liquids allows to precisely tune their physical properties, like the dc conductivity. Moreover, these mixtures enable the gradual modification of the fragility parameter, which is believed to be a measure of the complexity of the energy landscape in supercooled liquids. The physical origin of this index is still under debate; therefore, mixing ionic liquids can provide further insights. From the chemical point of view, tuning ionic liquids via mixing is an easy and thus an economic way. For this study, we performed detailed investigations by broadband dielectric spectroscopy and differential scanning calorimetry on two mixing series of ionic liquids. One series combines an imidazole based with a pyridine based ionic liquid and the other two different anions in an imidazole based ionic liquid. The analysis of the glass-transition temperatures and the thorough evaluations of the measured dielectric permittivity and conductivity spectra reveal that the dynamics in mixtures of ionic liquids are well defined by the fractions of their parent compounds.

show abstract

Section: Dielectric Spectroscopysupporting

confidence: 69%

Dielectric study on mixtures of ionic liquids

Thoms

Sippel

Reuter

et al. 2017

Sci Rep

View full text Add to dashboard Cite

show abstract

“…25 Xu et al 26 studied qualitative fragilities of aprotic ionic liquids using the T gscaled Arrhenius plot of viscosity, and the fragility of the ILs was found to range from intermediate to very fragile, depending on the ionic structure. In a quantitative study of m-fragility for a series of n-alkylimidazolium tetrafluoroborate with different alkyl chain length, Leys and co-workers 27 reported that alkyl chain length had a little effect.…”

Section: Introductionmentioning

confidence: 98%

Protic Ionic Liquids Based on Decahydroisoquinoline: Lost Superfragility and Ionicity-Fragility Correlation

et al. 2011

View full text Add to dashboard Cite

Physicochemical properties, ionicity, and fragility for protic ionic liquids (PILs) based on the protonation of the extremely fragile molecular liquid decahydroisoquinoline (DHiQ) by various Brønsted acids have been studied. The ionicity was evaluated using the Walden plot diagnostic, while the m-fragility (slope of T(g)-scaled Arrhenius plot at T(g)) was quantitatively measured by the Moynihan-Wang-Velikov variable scan rate, differential scanning calorimetry, method. DHiQ-derived PILs prove to cover the whole range of IL ionicities from poor IL to good IL, and even superionic, assessed from the Walden plot, depending on the choice of Brønsted acid. We find that the superfragile character of the parent DHiQ becomes completely suppressed upon conversion to ionic liquid, the initial value m = 128 sinking to m = 45-91 for the ionic liquid. Such values are in the intermediate to fragile range. The DHiQ-based PIL showing superionic behavior, anion [HSO(4)(-)], proves to be the case with the lowest m value (m = 45) so far reported for either aprotic or protic ILs. Both low fragility and dry proton conductivity can be attributed to an extended hydrogen bond network that is set up by the hydrogensulfate anion. The good DHiQ PILs have m values similar to those reported for typical aprotic ILs (m = 60-80), while the poor DHiQ PILs in which proton transfer from acid to base is weak show some memory of the parent fragility. Thus, a correlation of ionicity with m-fragility is characteristic of this system. A range of noncrystallizing, and also nonglassforming, behavior is observed in this series of compounds, suggesting a possible test for ideal glassformer existence.

show abstract

“…4 Broadband impedance spectroscopy has been extensively used to characterize ion transport and dielectric relaxation processes in ionic liquids. [5][6][7][8][9] In this method, low ac electric fields are applied, and the linear current response is measured. However, when the ac electric fields applied to ionic conductors (solid and liquid) are increased to values beyond 50-100 kV/cm, the current response becomes nonlinear.…”

Section: Introductionmentioning

confidence: 99%

Nonlinear ion transport in the supercooled ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide: Frequency dependence of third-order and fifth-order conductivity coefficients

Patro

Burghaus

Roling

2015

The Journal of Chemical Physics

View full text Add to dashboard Cite

We have carried out nonlinear ion conductivity measurements on the supercooled ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide[C6mim][NTf2] by applying ac electric fields with amplitudes up to about 200 kV/cm. At these field amplitudes, 3ω and 5ω harmonic components in the current response were detected, and the higher-order conductivity coefficients σ3 (1),σ3 (3),σ5 (3), and σ5 (5) were determined. The frequency and temperature dependence of these conductivity coefficients was analyzed in detail. The most important findings were the following: (i) The third-order spectra σ3 (1) and σ3 (3) exhibit very similar values in the dc plateau regime but differ considerably in the dispersive regime. The same was observed for the fifth order spectra σ5 (3) and σ5 (5). (ii) In the dispersive regime, the third-order spectra display a minimum, while the fifth-order spectra display a maximum. (iii) The frequencies of these minima and maxima are thermally activated with the same activation energy as the low-field dc conductivity σ1,dc, whereas the dc values of the higher-order conductivity coefficients, σ3,dc and σ5,dc, are characterized by lower activation energies.

show abstract

Influence of the anion on the electrical conductivity and glass formation of 1-butyl-3-methylimidazolium ionic liquids

Cited by 67 publications

References 48 publications

Dielectric study on mixtures of ionic liquids

Dielectric study on mixtures of ionic liquids

Protic Ionic Liquids Based on Decahydroisoquinoline: Lost Superfragility and Ionicity-Fragility Correlation

Nonlinear ion transport in the supercooled ionic liquid 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide: Frequency dependence of third-order and fifth-order conductivity coefficients

Contact Info

Product

Resources

About