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Sustainable ionic liquids are promising compounds in green chemistry applications. While using them as solvent or reaction media is an important step towards more environmentally friendly chemistry, their synthesis is usually expensive and not green at all. Herein, a benign route to synthesize task ‐ specific ionic liquids is presented, offering several possible functionalities in the cation and anion (artwork by D. Kraban). More information can be found in the Full Paper by C. Liedel et al. on page 11810. [ABSTRACT FROM AUTHOR]

• In this paper, we report the corrosion inhibition of amino acid imidazole ionic liquids ([CyVIm][AA]ILs) on mild steel in neutral media, which has not been studied before. • In addition, the corrosion inhibition performance of [CyVIm][AA]ILs in neutral media was evaluated comprehensively by a combination of experiments and simulations as well as an in-depth investigation of the corrosion inhibition mechanism. The corrosion inhibition properties of three amino acid imidazole ionic liquids ([CyVIm][AA]) as corrosion inhibitors for mild steel in a 3.5 wt% NaCl corrosion medium were evaluated by electrochemical measurements. The polarization experiments show that [CyVIm][AA] influences anode reaction processes, demonstrating that [CyVIm][AA] is an anodic inhibitor type corrosion inhibitor. [CyVIm]Try outperforms [CyVIm]His and [CyVIm]Pro in terms of corrosion inhibition. The results of surface analysis and quantum chemical calculations show that [CyVIm]Try can form a protective film on the surface of mild steel and inhibit surface corrosion. Furthermore, by applying molecular dynamics simulations, after investigating the corrosion inhibitor adsorption trends on the Fe (1 1 0) surface, the interaction order between the molecular framework of the Fe corrosion inhibitor and the Fe (1 1 0) surface for entanglement was determined. According to the radial distribution function, the corrosion inhibitor adsorption mode on the metal surface is composite adsorption with chemisorption as the major mode and physical adsorption as the secondary mode. [ABSTRACT FROM AUTHOR]

This work presents a comparative study of the electrochemical behaviour, on a glassy carbon electrode, of dissolved EuCl 3 in two chlorobasic ionic liquids, the 1-ethyl-3-methylimidazolium chloride, C 2 mimCl, and the 1-buthyl-3-methylimidazolium chloride, C 4 mimCl, over the temperature ranges 363–398 K and 343–363 K respectively. In both media, the electro-reduction of EuCl 6 3 − takes place via only one electrochemical step EuCl 6 3 − /EuCl 6 4 − . The electrochemical system EuCl 6 4 − /Eu(0) has not been observed within the electrochemical window of both ILs, due to the prior reduction of the respective imidazolium cation from the solvents, which inhibits the electro-extraction of Eu(0) from the media on the GC electrode. The paper describes how several electrochemical techniques (e.g. cyclic voltammetry (CV), convolutive potential sweep voltammetry (CPSV), steady state voltammetry (SSV), chronopotentiometry (CP) and chronoamperometry (CA)) have been used experimentally: i) verifying assumptions used in their theoretical analysis, and ii) ensuring reproducible conditions at the electrode/electrolyte interface, with the aim to obtain high-precision measurements of the diffusion coefficient of EuCl 6 3 − . In order to know if there are discrepancies between the obtained data, a two-way analysis of variance, ANOVA, has been carried out. The analysis has shown that with a 95% confidence level there are no significant differences between the diffusion coefficients obtained by the different techniques. On the other hand, the diffusion coefficient of EuCl 6 3 − increases with the temperature following the Arrhenius law, being the activation energy for diffusion 40.4 ± 2.6 and 60.2 ± 1.8 kJ mol − 1 in C 2 mimCl and C 4 mimCl respectively. The dimensionless Schmidt numbers, defined as the ratio between solvent viscosity and solute diffusivity ( Sc = ν/D), have also been calculated to characterise the solute global mass transport through its environment. On the GC electrode, the electro-reduction of EuCl 6 3 − to EuCl 6 4 − is a quasi-reversible process. Accurate values of the kinetic parameters (i.e. the intrinsic rate constant of charge transfer, k 0 , and the charge transfer coefficient, α), as well as the reversible half wave potential, E r 1/2 , have been obtained for the first time in the mentioned ionic liquids, by simulation of the cyclic voltammograms and logarithmic analysis of the voltammograms and convoluted curves. [ABSTRACT FROM AUTHOR]

We report the synthesis of task-specific imidazolium ionic compounds and ionic liquids with key functionalities of organic molecules from electro-, polymer-, and coordination chemistry. Such products are highly functional and potentially suitable for technology applications even though they are formed without elaborate reactions and from cheap and potentially green reagents. We further demonstrate the versatility of the used synthetic approach by introducing different functional and green counterions to the formed ionic liquids directly during the synthesis or after metathesis reactions. The influence of different cation structures and different anions on the thermal and electrochemical properties of the resulting ionic liquids is discussed. Our goal is to make progress towards economically competitive and sustainable task-specific ionic liquids. [ABSTRACT FROM AUTHOR]

Thiocyanate-functionalized ionic liquids (ILs) 1-butyl-3-methylimidazolium thiocyanate [BMIM][SCN], 1-ethyl-3-methylimidazolium thiocyanate [EMIM][SCN], and 3-methylimidazolium thiocyanate [MIM][SCN], with varying chain lengths, were synthesized by using metathesis followed by ion exchange under reflux conditions. These ILs were investigated for their application as electrolyte with a ZnFe2O4 nanoflake-based supercapacitor electrode; they exhibited significantly better performance than any other previously reported ILs used as electrolytes. [BMIM][SCN] showed higher specific capacitance (781 F g-1), cycle stability (95 % retention, 3000 cycle), and energy density (156 W h kg-1) than [EMIM][SCN] (590 F g-1, 86 % retention, and 78 W h kg-1) and [MIM][SCN] (250 F g-1, 80 % retention, and 50 W h kg-1). The ZnFe2O4 nanoflake electrodes were able to deliver an energy density of 156 W h kg-1 even at an extra high power density of 7.11 kW kg-1 in [BMIM][SCN] electrolyte, justifying its utility as a potential electrolyte. Furthermore, the effect of how the hydrated ions of the ILs in aqueous media influence the overall performance of the supercapacitor was studied systematically and found to be contrary to the reported trend and use of pure ILs as electrolytes. [ABSTRACT FROM AUTHOR]

Successful electrodeposition of aluminium from ionic liquids has been long achieved scientifically. Nevertheless, standard industrial procedures have not yet been established due to the difficulties associated with using closed system filled with inert gas for the electrodeposition process. This paper presents a new methodology in which electrodeposition of aluminium is conducted in air, after preparation of ionic liquids in a glove box and covering them by a nonwater-absorbable layer of particular organic compound. This compound is stable and shows no reaction with the ionic liquid. Using this new methodology, functional aluminium layers were successfully deposited from a first generation ionic liquid AlCl 3 /1-ethyl-3-methylimidazolium chloride – [EMIm]Cl – (60/40 mol%) on low carbon steel. Cyclic voltammetry (CV) measurements revealed that there was no significant difference in electrochemical properties characteristic of Al deposition when conducted in open air. SEM/EDX assessments showed that uniform, dense and adherent Al layers were obtained. Adherence of Al to the steel substrate was improved via in-situ electrochemical etching. [ABSTRACT FROM AUTHOR]

A novel, eco-friendly method for the activation of lignin by controlled oxidation was studied. The results obtained for six acidic imidazolium ionic liquids containing the hydrogen sulfate anion were compared. The key goal of this research was to increase the content of carbonyl groups in the lignin structure because these may play the main role in the transport of protons and electrons in active materials for electrochemical applications. By means of a variety of analytical techniques (FTIR, 13C CP/MAS NMR, and X-ray photoelectron spectroscopy; selected reactions to determine the presence of carbonyl groups; SEM; zeta-potential analysis; thermogravimetric analysis/ differential thermogravimetric analysis; and porous structure analysis), it was determined that the product obtained after treatment with 3-cyclohexyloxymethy-1-methylimidazolium hydrogen sulfate had favorable properties, in terms of the target application. Electrochemical tests proved that the obtained materials could be used as anodes in lithium batteries. The results show that the activation of lignin with ionic liquids can increase its capacity and maintain stability. [ABSTRACT FROM AUTHOR]

The electrocatalytic activity of synthesized quasi-spherical Pt nanoparticles (NPs) has been studied, taking as a model the CO electrooxidation reaction in two imidazolium-based ionic liquids such as 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [Cmim][NTf] and 1-butyl-3-methylimidazolium tetrafluoroborate [Cmim][BF]. In particular, the effect of (i) water content, (ii) temperature, and (iii) nature of the room-temperature ionic liquid (RTIL) on the electrocatalytic behavior of these Pt NPs has been systematically evaluated. The obtained results show how important are those parameters, since the CO oxidation peak potential exhibits a great sensitivity depending on the water content, temperature, and nature of the RTIL used. Interestingly, the charge density associated with the CO electrooxidation peak strongly depends on the nature of the ionic liquid, which reflects the complexity of this electrocatalytic reaction in this media. Moreover, Pt NP electrocatalyst degradation in those RTILs, considered as a loss of electrochemically active area, has been evaluated and shows high stability despite the extreme potentials afforded in RTILs. [ABSTRACT FROM AUTHOR]

The electrochemical behavior of Sn(II) was studied at 25 °C in three different room temperature ionic liquids (1-ethyl-3-methylimidazolium dicyanamide (EMI-DCA), 1-butyl-1-methylpyrrolidium bis-(trifluoromethanesulfonyl)imide (BMP-NTf), 1-ethyl-3-methylimidazolium bis-(trifluoromethanesulfonyl)imide (EMI-NTf)). The Sn(II) was introduced into EMI-NTf by anodic dissolution with a current efficiency of almost 100 %. The diffusion coefficient of Sn(II) was compared in three ionic liquids at different temperatures. In addition, the morphology of Sn deposits on the inert substrate Mo obtained from three ionic liquids at 25 °C was characterized. This study also shows that the copper-tin alloy could be achieved in EMI-NTf by the electrodeposition method and subsequent thermal treatment. [ABSTRACT FROM AUTHOR]

Ionic liquid (IL) monomers are receiving increased attention due to their versatile range of application, especially in the electrochemical and electromechanical fields. Within this study, imidazole-based ILs containing a polymerizable methacrylate (MA) group were synthesized to examine their influence on the viscosity and reactivity of typical (meth)acrylates. The IL-MAs were prepared from 1-butylimidazole and bromo methacrylates with different spacer lengths (C2–C6). The best results with respect to physicochemical properties and double bond conversions could be obtained for ILs with C3and C6spacers. Bulk polymerizations exhibited unusually high reactivity and double-bond conversion compared with typical mono-methacrylates. Addition of 10 wt% IL-MA to reactive diluents like hexane-1,6-diol diacrylate caused only minor reduction in reaction rate but increased final double bond conversion compared with the pure diacrylate. [ABSTRACT FROM AUTHOR]