Protic ionic liquid

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Tribological properties of amorphous carbon films obtained by electrodeposition from DMF using 2HEAL protic ionic liquid as dopant

Tribological properties of amorphous carbon films obtained by electrodeposition from DMF using 2HEAL protic ionic liquid as dopant

One of the most important parameters in the electrodeposition pro cess is the electrolyte composition. In this work N N; DiMethylFormamide (DMF) (FMaia 99%) was tested as electrolytes, as well as mixtures of DMF and 2 HydroxyEthylAmine Lactate (2HEAL), used as dopant, in order to increase the electrolyte conductivity, it is common to use ionic liquids as support electrolyte in electrodeposition process [26 29] . Normally, aprotic ionic liquids are used in this way, however this kind of ionic liquid have high cost and low stability, for this reason in this work a protic ionic liquid is used. The main difference of protic ionic liquids compared to the traditional aprotic is the presence of at least a proton, which is/are able to promote extensive hydrogen bonding [30] . In addition this family of ionic liquids are interesting alter native due their low cost and simple synthesis rout [31] . Three concen trations of this ionic liquid in the electrolyte were tested: 0.03 vol% (DMF30LI), 0.05 vol% (DMF50LI) and 0.1 vol% (DMF100LI).
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Tribological properties of amorphous carbon films obtained by electrodeposition from DMF using 2HEAL protic ionic liquid as dopant

Tribological properties of amorphous carbon films obtained by electrodeposition from DMF using 2HEAL protic ionic liquid as dopant

One of the most important parameters in the electrodeposition pro cess is the electrolyte composition. In this work N N; DiMethylFormamide (DMF) (FMaia 99%) was tested as electrolytes, as well as mixtures of DMF and 2 HydroxyEthylAmine Lactate (2HEAL), used as dopant, in order to increase the electrolyte conductivity, it is common to use ionic liquids as support electrolyte in electrodeposition process [26 29] . Normally, aprotic ionic liquids are used in this way, however this kind of ionic liquid have high cost and low stability, for this reason in this work a protic ionic liquid is used. The main difference of protic ionic liquids compared to the traditional aprotic is the presence of at least a proton, which is/are able to promote extensive hydrogen bonding [30] . In addition this family of ionic liquids are interesting alter native due their low cost and simple synthesis rout [31] . Three concen trations of this ionic liquid in the electrolyte were tested: 0.03 vol% (DMF30LI), 0.05 vol% (DMF50LI) and 0.1 vol% (DMF100LI).
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Charge storage mechanism of α-MnO 2 in protic and aprotic ionic liquid electrolytes

Charge storage mechanism of α-MnO 2 in protic and aprotic ionic liquid electrolytes

faradaic contribution is triggered and can be explained by the insertion of Li þ in MnO 2 . No synergistic effect of protons and Li þ can be found for the protic ionic liquid, suggesting that the cations efficiently block the access to the surface for the alkali ions. Overall our results show that a faradaic contribution can be exploited also at high scan rates when using ionic liquids, but that the relatively low conductivity of the electrolyte limits the high-power performance. Thus, to take ionic liquid-based electrolytes towards application, new systems with high conductivity (low viscosity) need to be developed. Alternatively, one can consider the addition of a small fraction of organic solvents in order to improve the conductivity. It has previously been shown for Li-batteries that the addition of a small amount of organic solvent improves the performance without sacrificing the unique properties of ionic liquids in terms of electrochemical and thermal stability [ 40 ], and this might also be a viable way forward in hybrid supercapacitor applications.
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Transferable, Polarizable Force Field for Electrolytes, Protic Ionic Liquids and Deep Eutectic Solvents

Transferable, Polarizable Force Field for Electrolytes, Protic Ionic Liquids and Deep Eutectic Solvents

(Dated: 21 January 2021) The polarizable CL&Pol force field presented in our previous study, Transferable, Polarizable Force Field for Ionic Liquids (J. Chem. Theory Comput. 2019, 15, 5858, DOI: 10.1021/acs.jctc.9b00689 ), is extended to electrolytes, protic ionic liquids, deep eutectic solvents, and glycols. These systems are problematic in polarizable simulations because they contain either small, highly charged ions or strong hydrogen bonds, which cause trajectory instabilities due to the pull exerted on the induced dipoles. We use a Tang-Toennies function to dampen, or smear, the interactions between charges and induced dipole at short range involving small, highly charged atoms (such as hydrogen or lithium), thus preventing the “polarization catastrophe”. The new force field gives stable trajectories and is validated through comparison with experimental data on density, viscosity, and ion diffusion coefficients of liquid systems of the above-mentioned classes. The results also shed light on the hydrogen-bonding pattern in ethylammonium nitrate, a protic ionic liquid, for which the literature contains conflicting views. We describe the implementation of the Tang-Toennies damping function, of the temperature-grouped Nosé-Hoover thermostat for polarizable molecular dynamics and of the periodic perturbation method for viscosity evaluation from non-equilibrium trajectories in the LAMMPS molecular dynamics code. The main result of this work is the wider applicability of the CL&Pol polarizable force field to new, important classes of fluids, achieving robust trajectories and a good description of equilibrium and transport properties in challenging systems. The fragment-based approach of CL&Pol will allow ready extension to a wide variety of protic ionic liquids, deep eutectic solvents and electrolytes.
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Understanding the destructuration of starch in water–ionic liquid mixtures

Understanding the destructuration of starch in water–ionic liquid mixtures

In recent years, the performance of ionic liquids (ILs) as solvents for biopolymers has generated lots of interest. ILs are room-temperature molten salts; since they present high thermal stability and are not volatile, it has been reported that they offer an alternative to common organic solvents. For this reason and because they are easily recyclable, and even some of them are biodegradable, 4 they have been classified as ‘green solvents.’ For these reasons, they have attracted enormous attention over the past decade, becoming a very important area of research. 5 Over the last few years, the use of ILs to dissolve and process starch has been reported. 6–10 While the first reports focusing on ionic liquids containing chlorine anions showed strong depolymerisation of starch, thus limiting poten- tial applications, 9 more recent works on acetate based ionic liquids are more promising, 8 despite the fact that no clear evaluation of starch degradation in such systems has been communicated by the authors. In the presence of chlorine anions, the macromolecular degradation of starch has been related to the acidic hydrolysis of glycosidic bonds. 6,9,11–13 According to Mateyawa et al. 8 the presence of acetate based
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Charge Storage Mechanisms of Single-Layer Graphene in Ionic Liquid

Charge Storage Mechanisms of Single-Layer Graphene in Ionic Liquid

(corresponding to the concentration) and the SLG electrode contains 336 carbon atoms. The carbon atoms in SLG electrode were fixed in all relaxation processes. The ultra-fine quality preset was adopted for geometry optimization and energy calculation. The electrostatic and van der Waals summation was calculated by Ewald method. It should be noted that this model is not suitable to predict the cluster formation during charging process because of the difference between the vacuum environment of ions in modelling and the liquid electrolyte in real measurement.
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Thermodynamics of Cellulose Dissolution in an Imidazolium Acetate Ionic Liquid

Thermodynamics of Cellulose Dissolution in an Imidazolium Acetate Ionic Liquid

Natural cellulose cannot be dissolved in usual solvents under mild conditions. This fact prevents many possible applications of this cheap and abundant natural polymer. 1 In 2002, Swatloski et al. 2 reported that ionic liquids could dissolve high amounts of cellulose at moderate temperatures. These molten salts, liquid bellow 100 1C, are thermally stable and non-volatile, decreasing the risk of pollution and facilitating recycling. 3 Ionic liquids based on acetate or chloride anions, combined with small alkylimidazolium cations, were found to be the most promising as they could dissolve large amounts of cellulose (415 wt%). 4,5 Acetate-based ionic liquids, being less viscous, seem to present some advantages over chloride-based ionic liquids, namely improved mass transport and faster kinetics of dissolution. 6 It was recently demonstrated that the addition of co-solvents, like dimethyl sulfoxide, DMSO, to 1-butyl-3-methylimidazolium acetate, [C4C1Im][OAc], significantly decreases the time necessary for the cellulose dissolution. 7 DMSO does not interact with the polymer in solution, its role being just to increase the fluidity of the medium. 8 As is the case for other polymers, cellulose dissolution in ionic liquids seems to be controlled kinetically. The thermodynamics of the dissolution process are rarely treated specifically, even when arguments involving molecular interactions or hydrogen bond formation are used to explain the behavior of cellulose in the presence of ionic liquids. 9 The dissolution of high molecular weight polymers is always associated with small positive entropy
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Characterization of ion Cluster fragmentation in ionic liquid ion sources

Characterization of ion Cluster fragmentation in ionic liquid ion sources

Abstract Ion electrospray propulsion is a cutting-edge micropropulsion technology that could revolutionize the capabilities of microsatellites. Ion electrospray thrusters could also be used on large spacecraft for precision attitude control applications such as gravity wave detection and exoplanet imaging. Novel room temperature molten salts, called ionic liquids, are used as propellant, which are composed purely of positive and neg- ative molecular ions. When exposed to strong electric fields, ions and metastable clusters of ions are evaporated from the bulk liquid surface. The free ions and ion clusters can be accelerated to high velocities, producing thrust at high specific im- pulse. The performance of ion electrospray thrusters is affected by the composition of the ion beam and the amount of ion clusters that break apart during the acceleration phase. To improve thruster performance, a better understanding of the fundamental physics of ion evaporation and cluster break-up is needed.
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Electrodeposition Growth of Oriented ZnO Deposits in Ionic Liquid Media

Electrodeposition Growth of Oriented ZnO Deposits in Ionic Liquid Media

= 0.005 M 17 ), the first steps of electrodeposition are similar to the high potential deposition. At the beginning, only O2 is reduced and the thin layer of ZnO is formed. After a certain time (400s) a thin layer is formed (Fig. 3a ) and the growth of second ZnO morphology starts; further deposition of Zn occurs (after 1500 s) due to a decrease in concentration of oxygen in the vicinity of the electrode (the flux of oxygen is not sufficient to react with all Zn 2 + near the double layer). This is also confirmed by EQCM measurements (Fig. 2 ), where alter- native reactions of zinc and oxygen reduction occur, because the M/z value varies between 41 and 33 at low potentials. In contrast, when the deposition is done at RT no zinc reduction occurred at very low po- tential ( −1.85 V), even after a long time (4h), indicating that the Zn 2 + reduction is totally suppressed (Fig. 3a ). Changes in the concentration of molecular oxygen in the bath at low and high temperatures, change of the reaction mechanism (formation of peroxides that may form a blocking diffusion layer) as well as changes in the coordination of Zinc cations upon heating could be at the origin of such a difference. Turning to the deposit growth direction we show that it can be switched from polar (along 00l) to non polar (along hk0) depend- ing upon the composition of the electrodeposition bath. It was earlier reported that highly polar solvents like water, 30 DMSO 31 or mixture of DMSO with IL (as we reported) lead to deposits either oriented in the polar direction or with random orientation. Here we have pushed this observation further by showing that solvents with low dielectric constant EMImTFSI ( ε = 12.0) 44 and more so toluene ( ε = 2.38) lead to deposits oriented along the non-polar direction, clearly stressing the importance of solvent dielectric constant in ruling the ZnO growth direction. Moreover, we show that using ionic liquid conjointly with another solvent such as toluene enables to overcome the poor ionic liquid viscosity so as to improve transfer phenomena. Needless to say that dilution effect (IL + Solvent) can also influence the coordination
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New catalytic systems based on carbon nanotubes supported ionic liquid phase

New catalytic systems based on carbon nanotubes supported ionic liquid phase

experiments were done without loss of activity for 9 runs and without catalytic phase leaching, in contrast to commercial heterogeneous Pd/Al 2 O 3 catalyst, which, under the same conditions, presents deactivation after the third run. Pt nanoparticles supported on an ionic liquid modified magnetite nanoparticles where used as catalyst for the hydrogenation of α,β-unsaturated alkynes and aldehydes. 121 The reaction was found to be selective in the hydrogenation of alkynes to cis-alkenes and α,β -unsaturated aldehydes to the corresponding alcohols. The authors explain the high selectivity towards cis- alkenes on the basis of a support effect. The magnetic support can act as bulky ligand avoiding the access of alkenes to the metal nanoparticles surface. The magnetite nanosupport can also polarize the Pt nanoparticles, making them partially positive and thus activate the polar functional group of the α,β-unsaturated aldehydes, giving alcohols. The system acts like a homogeneous catalyst being dissolved in a solvent, but it exhibits a catalytic heterogeneous behaviour and in consequence can be separated by an external magnetic field and thus recycling.
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Electrodeposition Growth of Oriented ZnO Deposits in Ionic Liquid Media

Electrodeposition Growth of Oriented ZnO Deposits in Ionic Liquid Media

Deposit morphology.— Figures 4 , 5 present the SEM images of individual deposits with at first the reference deposit, obtained at 100 ◦ C with a 0.12 M Zn(TFSI) 2 solution in EMImTFSI when clamp- ing the potential at −1.00 V for 2 hours, and which is transparent. It is composed of a thin compact layer ( ∼500nm) with, in addition, 200–300 nm grains on top as can be seen in Figures 4a and 4b . It is worth noting that cracks are not initially present in the film but are developing upon long beam exposure (annex Fig. 5 *). To grasp more insight in the primary particles we carried TEM measurements which indicate that the deposit is made of very small crystallites (6 nm) as deduced by HRTEM measurement (annex Fig. 6 *). From EDX we also spotted peaks associated to F and S suggesting the presence of residual ionic liquid that could not be fully eliminated even after several washings with methane dichloride. This does not come as a total surprise since we previously experienced a similar surface contamination for all the powders we have so far prepared by ionothermal synthesis even after copious washing either in dimethyl chlorine or ethyl acetate. 42
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Nanostructured thermosets from ionic liquid building block–epoxy prepolymer mixtures

Nanostructured thermosets from ionic liquid building block–epoxy prepolymer mixtures

The objective of this work is to design ionic liquid con- taining networked polymers to be employed as new polymer electrolytes. The versatility of the ionic liquid due to the cation/anion combination is an excellent way to develop chemically cross-linked so gel like materials. One condition must be respected through the design of epoxy–IL electrolyte: (i) the creation of ionic channels within the polymer to ensure the conduction properties. For this reason, IL based on tri- hexyl(tetradecyl)phosphonium with dicyanamide anion has been used as functional additives (5–30 phr) to perform epoxy network with nanostructuration combined with good mechanical performance. Moreover, the structuration of IL in epoxy network has been highlighted for the rst time by TEM and AFM.
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Correlation between thermostability and stability of glycosidases in ionic liquid

Correlation between thermostability and stability of glycosidases in ionic liquid

galactosidases (Thermotoga maritima and Bacillus stearothermophilus) were studied in different hydrophilic ionic liquid (IL)/water ratios. For the ILs used, the glycosidases showed the best stability and activity in 1,3-dimethylimidazolium methyl sulfate [MMIM][MeSO 4 ] and 1,2,3- trimethylimidazolium methyl sulfate [TMIM][MeSO 4 ]. A close correlation was observed between

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Ionic liquid-assisted morphosynthesis of gold nanorods using polyethyleneimine-capped seeds

Ionic liquid-assisted morphosynthesis of gold nanorods using polyethyleneimine-capped seeds

emimHexSO 4 IL is monitored by DLS and reported in Fig. 5. The growth medium of conditions A (resp. B) in Fig. 3 is modelled by an aqueous solution of 10 mM CTAB, 4.1 mM (resp. 8.2 mM) IL and 0.38 mM PEI to which the Au seeds are added. The DLS spectra of this reference medium show the presence of a single distribution of 6 nm diameter CTAB micelles (Fig. 5A). The spread of the apparent diameter is quite large (standard deviation, s, is 2.5 nm) indicating an inhomogeneous and fluctuating distribu- tion of micelle sizes ascribed to the destructuring action of PEI. However, upon addition of extra IL up to a final concentration of 8.2 mM, the single distribution shifts to an apparent diameter of 11 nm with a marked reduction of the data spread (s = 1 nm, Fig. 5B). This suggests that the IL counteracts the entropic effect of PEI and interacts significantly with CTAB layers, most likely by van der Waals interaction between the cetyl and hexyl chains and the catanionic interactions of the ammonium, sulfate and emim ionic species. 44 This interaction results in the formation of very monodisperse CTAB/IL colloidal objects of larger size than pure CTAB micelles. When the pure IL is replaced by an aliquot of Au seeds in IL (Fig. 5C), very similar single-peaked DLS spectra are obtained with a narrow data dispersion (s = 1 nm) but centered on an average value of 13 nm. This suggests that the sub-5 nm Au seeds could be encapsulated in the organized CTAB/IL spherical colloid. Interestingly, when extra IL is added to mimic the growth media B or D, the average diameter increases even more to 18 ¡ 0.5 nm (Fig. 5D). The diameter increase by 5 nm and a reduction of the polydispersity from s = 3 nm to s = 1.5 nm is also observed for a twenty-fold increase of the seed concentration (Fig. 5E–F).
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Electroswitchable red-NIR luminescence of ionic clustomesogen containing nematic liquid crystalline devices.

Electroswitchable red-NIR luminescence of ionic clustomesogen containing nematic liquid crystalline devices.

S20. This difference could eventually be explained by the microsegregation of Kat 2 Mo 6 I 14 in the host matrix. This phenomenon would increase locally the viscosity of the mixture preventing Kat 2 Mo 6 I 14 microagregates to properly react to the electric field. This should induce in principle a decrease of the photoluminescence contrast. The exact origin of this reversible switch in the luminescence intensity may be imparted to many cooperating (birefringence of the LC host, birefringence of the hybrid, emission anisotropy…) and is not yet fully understood. However, several observations can be made at this stage: i) E44 was chosen for its high birefringence (Δn=0.26 at λ=589 nm) but can only be partially responsible for the intensity modulation that is about 52%; ii) as the switch is fully reversible, clustomesogens appear to be stable under voltage application despite their ionic character (no apparent charge separation); iii) this stability implies also that the applied electric field is not high enough to oxidize or reduce the metal clusters from a luminescent to a non-luminescent form; iv) luminescence properties are only due to anionic cluster moieties. As these entities are isotropic, the use of an electric field to align the molecules should not modify their ability to emit light. Therefore, according to our observations, it seems that the all hybrid supramolecular compounds has to be taken into account when one consider the emission properties of such system in the LC phase. In this context, one might also consider the ability of the CB units to act as antenna with the metallic cluster. Indeed, their orientation in the LC cell influences not only their ability to
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NMR Study of Ion Dynamics and Charge Storage in Ionic Liquid Supercapacitors

NMR Study of Ion Dynamics and Charge Storage in Ionic Liquid Supercapacitors

necessitating a full deconvolution that accounts for the spinning sidebands, as we carried out here. Overall, the charge storage mechanism is summarized as follows. The pores are initially wetted with ionic liquid, with 1.6 mmol of in-pore ionic liquid per gram of material and an equal number of in-pore anions and cations. Charge storage then occurs by adsorption of counterions and desorption of co-ions, with TFSI − adsorption dominating charge storage in the positive electrode and TFSI − desorption dominating charge storage in the negative electrode. At the same time a smaller number of Pyr 13 + are adsorbed in the negative electrode and desorbed in the positive electrode during charging. We do not believe that the difference in the behavior of anions and cations is a kinetic effect, as supercapacitor cells were held at the studied voltages for relatively long times (1 h) compared to the time needed for current equilibration (at most 10 min). The volume of the ions is similar, suggesting that the origin of this phenomenon is not due to simple packing arguments. There are a number of possible causes of this effect, which include the following: (i) differences in the distribution of charge on the ions, (ii) steric effects due to differences in the shapes of the ions, and (iii) differences in the binding energies to the carbon. Further theoretical work and experiments must be done to explore these effects. We note that there are differences between the charging mechanism elucidated in our present Figure 3. Number of in-pore ions for cells (YP50F, Pyr 13 TFSI ionic
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Capacitive energy storage from -50 to 100 °C using an ionic liquid electrolyte

Capacitive energy storage from -50 to 100 °C using an ionic liquid electrolyte

To cite this version : Lin, Rongying and Taberna, Pierre-Louis and Fantini, Sébastien and Presser, Volker and Pérez, Carlos R. andMalbosc, François and Rupesinghe, Nalin L. and Teo, Kenneth B. K. and Gogotsi, Yury and Simon, Patrice. Capacitive energy storage from -50 to 100 °C using an ionic liquid electrolyte. (2011) The Journal of Physical Chemistry Letters, vol. 2 (n° 19). pp. 2396-2401. ISSN 1948-7185

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Ultrasound assisted crystallization of a new cardioactive prototype using ionic liquid as solvent

Ultrasound assisted crystallization of a new cardioactive prototype using ionic liquid as solvent

4. Dissolution studies 4.1. Dissolution experiments The dissolution profiles of LASSBio-294 recrystallized under dif- ferent crystallization conditions and oven-dried are shown in Fig. 14 . The recrystallized LASSBio-294 dissolved slower than the raw LASSBio- 294. For example, after 30 min, 41% of the recrystallized drug (Ex- periment 9) and 75% of the original crystals are dissolved. As already discussed, LASSBio-294 is very slightly soluble in water. Its solubility in aqueous medium with SDS 0.5% increases due to the formation of surfactant micelles and micellar solubilization of the drug. Further- more, the presence of the surfactant reduces the solid-liquid interfacial tension and increases wettability of the crystals LASSBio-294. These effects enhanced the dissolution of the LASSBio-294, explaining the higher dissolution rate of the original crystals. The results also showed that the application of ultrasound generated LASSBio-294 crystals with slower dissolution. However, when powders are examined in SEM ( Fig. 15 ), it appears that the dissolution of recrystallized LASSBio-294 depended on both factors, crystals morphology and agglomeration/ aggregation states: Dropwise without US (Experiment 9) > Quick without US (Experiment 5) > Quick with US (Experiment 6) > Dropwise with US (Experiment 10) (faster dissolution from less to more compact). No relationship was observed between the dissolution rate, residual solvent and mean size of the dry crystals. The dissolution profiles of the crystals obtained by spray drying are shown in Fig. 16 . As described above, the recrystallized LASSBio-294 dissolved slower than the raw LASSBio-294. However, spray-drying crystals dissolved more rapidly than those oven-dried ( Table 3 ). Spray drying favored the for- mation of smaller agglomerates, which disaggregated easier when dis- persed in the dissolution medium.
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NMR Study of Ion Dynamics and Charge Storage in Ionic Liquid Supercapacitors

NMR Study of Ion Dynamics and Charge Storage in Ionic Liquid Supercapacitors

2 H spectrum (Figure 6c) con firms the presence of acetonitrile in the carbon micropores. The broader resonances observed here (compared to say Figure 6a) may arise from chemical exchange of solvent molecules between the in-pore and the ex- pore environments. Spectra were also recorded for a sample containing YP50F and EMITFSI/dACN (see Supporting Information), with in-pore resonances again significantly narrowed compared to the sample without solvent. The large reductions of the in-pore line widths for anions and cations following the addition of acetonitrile show that its presence in the micropores greatly speeds up in-pore ionic di ffusion. On the basis of our multisite exchange simulations (see Supporting Information), we calculate a time scale of 13 μs for motion of in-pore TFSI for Pyr 13 TFSI/dACN, that is, in-pore di ffusion of TFSI − is 5.5 times faster following the addition of acetonitrile, representing a dramatic increase. For EMITFSI/dACN we calculate an identical time scale of 13 μs for in-pore TFSI, suggesting that the motion of in-pore anions is not significantly a ffected by different cations in the solvated electrolytes. We note that the di fference between the 19 F chemical shifts of the in- and ex-pore resonances decreases slightly from 6.6 to 5.7 ppm after adding solvent. We propose that the presence of acetonitrile slightly lengthens the average carbon −ion distances, giving rise to weaker ring current e ffects. This may be due to the partial solvation of the ions, though the increased exchange between the in-pore and the ex-pore environments may also have an e ffect.
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Liquid-liquid miscibility and volumetric properties of aqueous solutions of ionic liquids as a function of temperature

Liquid-liquid miscibility and volumetric properties of aqueous solutions of ionic liquids as a function of temperature

methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ([C 1 C 4 Pyr- ro][NTf 2 ]), butyltrimethylammonium bis(trifluoromethylsulfo- nyl)imide ([N 4111 ][NTf 2 ]). Prior to the study the volumetric properties, the phase behav- iour of the binary systems containing hydrophobic ILs was investi- gated in order to determine their mutual solubility with water. A nephelometric method [41,42] was used to detect cloud points. The volumetric properties are then investigated for IL mole frac- tions where only one liquid phase is observed. Excess molar vol- umes, defined as the difference between the actual molar volume of the mixture and that of an ideal solution at the same tempera- ture, pressure, and composition, represent the deviation from the ideal behaviour of the mixtures. These values were calculated for all the {IL + water} mixtures from density measurements per- formed at atmospheric pressure as a function of temperature be- tween (293 and 343) K at 5 K intervals and of the composition of the liquid mixture. In each case at least eight compositions for each binary system were examined.
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