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Showing papers on "Ionic liquid published in 2015"


Journal ArticleDOI
TL;DR: Using the applicability and extension of these parameters to describe and quantify the doubly ionic H-bond has been explored, and it is clear that doubly ionsicH-bonds cover the full range of weak through to very strong H- bonds.
Abstract: Ionic liquids (IL) and hydrogen bonding (H-bonding) are two diverse fields for which there is a developing recognition of significant overlap. Doubly ionic H-bonds occur when a H-bond forms between a cation and anion, and are a key feature of ILs. Doubly ionic H-bonds represent a wide area of H-bonding which has yet to be fully recognised, characterised or explored. H-bonds in ILs (both protic and aprotic) are bifurcated and chelating, and unlike many molecular liquids a significant variety of distinct H-bonds are formed between different types and numbers of donor and acceptor sites within a given IL. Traditional more neutral H-bonds can also be formed in functionalised ILs, adding a further level of complexity. Ab initio computed parameters; association energies, partial charges, density descriptors as encompassed by the QTAIM methodology (ρBCP), qualitative molecular orbital theory and NBO analysis provide established and robust mechanisms for understanding and interpreting traditional neutral and ionic H-bonds. In this review the applicability and extension of these parameters to describe and quantify the doubly ionic H-bond has been explored. Estimating the H-bonding energy is difficult because at a fundamental level the H-bond and ionic interaction are coupled. The NBO and QTAIM methodologies, unlike the total energy, are local descriptors and therefore can be used to directly compare neutral, ionic and doubly ionic H-bonds. The charged nature of the ions influences the ionic characteristics of the H-bond and vice versa, in addition the close association of the ions leads to enhanced orbital overlap and covalent contributions. The charge on the ions raises the energy of the Ylp and lowers the energy of the X–H σ* NBOs resulting in greater charge transfer, strengthening the H-bond. Using this range of parameters and comparing doubly ionic H-bonds to more traditional neutral and ionic H-bonds it is clear that doubly ionic H-bonds cover the full range of weak through to very strong H-bonds.

572 citations


Journal ArticleDOI
TL;DR: In this paper, the authors investigated the alkaline stability of 26 different quaternary ammonium groups (QA) for temperatures up to 160 °C and NaOH concentrations up to 10 mol L(-1) with the aim to provide a basis for the selection of functional groups for hydroxide exchange membranes in alkaline fuel cells and of ionic-liquid cations stable in basic conditions.
Abstract: The alkaline stability of 26 different quaternary ammonium groups (QA) is investigated for temperatures up to 160 °C and NaOH concentrations up to 10 mol L(-1) with the aim to provide a basis for the selection of functional groups for hydroxide exchange membranes in alkaline fuel cells and of ionic-liquid cations stable in basic conditions. Most QAs exhibit unexpectedly high alkaline stability with the exception of aromatic cations. β-Protons are found to be far less susceptible to nucleophilic attack than previously suggested, whereas the presence of benzyl groups, nearby hetero-atoms, or other electron-withdrawing species promote degradation reactions significantly. Cyclic QAs proved to be exceptionally stable, with the piperidine-based 6-azonia-spiro[5.5]undecane featuring the highest half-life at the chosen conditions. Absolute and relative stabilities presented herein stand in contrast to literature data, the differences being ascribed to solvent effects on degradation.

511 citations


Journal ArticleDOI
TL;DR: Deep eutectic solvents (DESs) have become more and more attractive in recent years due to their interesting properties and benefits, such as low cost of components, easy to prepare, tunable physicochemical properties, negligible vapor pressure, non-toxicity, biorenewability and biodegradability as mentioned in this paper.
Abstract: Deep eutectic solvents (DESs), also known as deep eutectic ionic liquids (DEILs) or low-melting mixtures (LMMs) or low transition temperature mixtures (LTTMs) in the literature, have become more and more attractive in recent years due to their interesting properties and benefits, such as low cost of components, easy to prepare, tunable physicochemical properties, negligible vapor pressure, non-toxicity, biorenewability and biodegradability. These eutectic mixtures have been widely used as green and sustainable media as well as catalysts in many chemical processes. This review focuses on recent advances using DESs in organic reactions including addition reactions, cyclization reactions, replacement reactions, multicomponent reactions, condensation reactions, oxidation reactions, and reducing reactions.

447 citations


Journal ArticleDOI
TL;DR: In this paper, a number of ionic liquids were synthesized with the goal of optimizing solvent cost and stability whilst demonstrating promising processing potential for cellulosic biorefinery, and they were compared to a benchmark system containing the IL 1-ethyl-3-methylimidazolium acetate [C2C1im][OAc].

385 citations


Journal ArticleDOI
TL;DR: In this article, the cooperative effect of CO2 with epoxides into cyclic carbonates with respect to the newly emerged ionic liquid (IL) technology is discussed from a multi-scale viewpoint.

351 citations


Journal ArticleDOI
TL;DR: In this article, a review of the general strategies for the design of innovative polymer electrolytes using poly(ionic liquid)s is presented, with a special attention given to the optimization of both the ionic monomer chemical structure and macromolecular architecture to achieve the highest possible polymer ionic conductivity.

330 citations


Journal ArticleDOI
TL;DR: In this paper, a detailed analysis of the relevant interfaces using surface science methods is presented, including the IL/vacuum or IL/gas interface, the solubility and surface enrichment of dissolved metal complexes, the support interface and the in situ monitoring of chemical reactions in ionic liquids are presented.
Abstract: Ionic liquids (ILs), salts with melting points below 100 °C, represent a fascinating class of liquid materials typically characterized by an extremely low vapor pressure. Besides their application as new solvents or as electrolytes for electrochemical purposes, there are two important concepts of using ILs in catalysis: Liquid–liquid biphasic catalysis and IL thin film catalysis. Liquid–liquid biphasic catalysis enables either a very efficient manner to apply catalytic ILs, e.g. in Friedel–Crafts reactions, or to apply ionic transition metal catalyst solutions. In both cases, phase separation after reaction allows an easy separation of reaction products and catalyst re-use. One problem of liquid–liquid biphasic catalysis is mass transfer limitation. If the chemical reaction is much faster than the liquid–liquid mass transfer the latter limits the overall reaction rate. This problem is overcome in IL thin film catalysis where diffusion pathways and thus the characteristic time of diffusion are short. Here, Supported Ionic Liquid Phase (SILP) and Solid Catalyst with Ionic Liquid Layer (SCILL) are the two most important concepts. In both, a high surface area solid substrate is covered with a thin IL film, which contains either a homogeneously dissolved transition metal complex for SILP, or which modifies catalytically active surface sites at the support for SCILL. In each concept, interface phenomena play a very important role: These may concern the interface of an IL phase with an organic phase in the case of liquid–liquid biphasic catalysis. For IL thin film catalysis, the interfaces of the IL with the gas phase and with catalytic nanoparticles and/or support materials are of critical importance. It has recently been demonstrated that these interfaces and also the bulk of ILs can be investigated in great detail using surface science studies, which greatly contributed to the fundamental understanding of the catalytic properties of ILs and supported IL materials. Exemplary results concerning the IL/vacuum or IL/gas interface, the solubility and surface enrichment of dissolved metal complexes, the IL/support interface and the in situ monitoring of chemical reactions in ILs are presented. Important concepts in catalysis with ionic liquids are reviewed, including Supported Ionic Liquid Phase (SILP) and Solid Catalyst with Ionic Liquid Layer (SCILL), along with the detailed analysis of the relevant interfaces using surface science methods.

318 citations


Journal ArticleDOI
TL;DR: Mixed matrix membranes derived from ionic liquid-modified ZIF-8 exhibited remarkable combinations of permeability and selectivity that transcend the upper bound of polymer membranes for CO2 /N2 andCO2 /CH4 separation.
Abstract: Fine-tuning of effective pore size of microporous materials is necessary to achieve precise molecular sieving properties. Herein, we demonstrate that room temperature ionic liquids can be used as cavity occupants for modification of the microenvironment of MOF nanocages. Targeting CO2 capture applications, we tailored the effective cage size of ZIF-8 to be between CO2 and N2 by confining an imidazolium-based ionic liquid [bmim][Tf2 N] into ZIF-8's SOD cages by in-situ ionothermal synthesis. Mixed matrix membranes derived from ionic liquid-modified ZIF-8 exhibited remarkable combinations of permeability and selectivity that transcend the upper bound of polymer membranes for CO2 /N2 and CO2 /CH4 separation. We observed an unusual response of the membranes to varying pressure, that is, an increase in the CO2 /CH4 separation factor with pressure, which is highly desirable for practical applications in natural gas upgrading.

298 citations


Journal ArticleDOI
TL;DR: Results show that, for a wide range of ionic liquids, the general AMBER force field can reproduce a variety of thermodynamic and transport properties with similar accuracy to that of other published, often IL-specific, force fields.
Abstract: We have applied molecular dynamics to calculate thermodynamic and transport properties of a set of 19 room-temperature ionic liquids. Since accurately simulating the thermophysical properties of solvents strongly depends upon the force field of choice, we tested the accuracy of the general AMBER force field, without refinement, for the case of ionic liquids. Electrostatic point charges were developed using ab initio calculations and a charge scaling factor of 0.8 to more accurately predict dynamic properties. The density, heat capacity, molar enthalpy of vaporization, self-diffusivity, and shear viscosity of the ionic liquids were computed and compared to experimentally available data, and good agreement across a wide range of cation and anion types was observed. Results show that, for a wide range of ionic liquids, the general AMBER force field, with no tuning of parameters, can reproduce a variety of thermodynamic and transport properties with similar accuracy to that of other published, often IL-specif...

274 citations


Journal ArticleDOI
TL;DR: This review of the interactions within nanoparticle dispersions in ionic liquids and of the structure of nanoparticle and ionic liquid hybrids provides guidance on the rational design of novel ionic Liquid-based materials, enabling applications in broad areas.
Abstract: Ionic liquids (ILs), defined as low-melting organic salts, are a novel class of compounds with unique properties and a combinatorially great chemical diversity. Ionic liquids are utilized as synthesis and dispersion media for nanoparticles as well as for surface functionalization. Ionic liquid and nanoparticle hybrid systems are governed by a combined effect of several intermolecular interactions between their constituents. For each interaction, including van der Waals, electrostatic, structural, solvophobic, steric, and hydrogen bonding, the characterization and quantitative calculation methods together with factors affecting these interactions are reviewed here. Various self-organized structures based on nanoparticles in ionic liquids are generated as a result of a balance of these intermolecular interactions. These structures, including colloidal glasses and gels, lyotropic liquid crystals, nanoparticle-stabilized ionic liquid-containing emulsions, ionic liquid surface-functionalized nanoparticles, and nanoscale ionic materials, possess properties of both ionic liquids and nanoparticles, which render them useful as novel materials especially in electrochemical and catalysis applications. This review of the interactions within nanoparticle dispersions in ionic liquids and of the structure of nanoparticle and ionic liquid hybrids provides guidance on the rational design of novel ionic liquid-based materials, enabling applications in broad areas.

273 citations



Journal ArticleDOI
TL;DR: In this article, the ionic conductivity of polymeric gel electrolyte membranes has been found to increase with increasing concentration of IL and attains a maximum value of 2 × 10−3 S cm−1 at 30 °C and ∼3 × 10 −2 S cm −1 at 130 °C.
Abstract: Ion conducting polymer gel electrolyte membranes based on polymer poly(vinylidene fluoride-co-hexafluoropropylene) PVdF-HFP, ionic liquid, 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide BMIMTFSI with and without the Li-salt (having the same anion i.e. the TFSI− anion) have been synthesized. Prepared membranes have been characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared (FTIR), differential scanning calorimetry, thermogravimetric analysis (TGA) and complex impedance spectroscopic techniques. Incorporation of IL in the polymer PVdF-HFP/polymer electrolyte (i.e. PVdF-HFP + 20 wt% LiTFSI) changes different physicochemical properties such as melting temperature (Tm), glass transition temperature (Tg), thermal stability, degree of crystallinity (Xc), and ionic transport behaviour of these materials. The ionic conductivity of polymeric gel electrolyte membranes has been found to increase with increasing concentration of IL and attains a maximum value of 2 × 10−3 S cm−1 at 30 °C and ∼3 × 10−2 S cm−1 at 130 °C. A high total ionic transference number >0.99 and the cationic transference number (tLi+) ∼ 0.22 with a wider electrochemical window (ECW) ∼ 4.0–5.0 V for the polymer gel electrolyte membrane containing higher loading of IL (∼70 wt% of IL) have been obtained. Temperature dependent ionic conductivity obeys Arrhenius type thermally activated behaviour.

Journal ArticleDOI
TL;DR: A highly energy-dense lithium-ion cell with an impressively long cycling life, maintaining over 75% capacity after 500 cycles, enabled by a stable half-cell coulombic efficiency.
Abstract: We are currently in the midst of a race to discover and develop new battery materials capable of providing high energy-density at low cost. By combining a high-performance Si electrode architecture with a room temperature ionic liquid electrolyte, here we demonstrate a highly energy-dense lithium-ion cell with an impressively long cycling life, maintaining over 75% capacity after 500 cycles. Such high performance is enabled by a stable half-cell coulombic efficiency of 99.97%, averaged over the first 200 cycles. Equally as significant, our detailed characterization elucidates the previously convoluted mechanisms of the solid-electrolyte interphase on Si electrodes. We provide a theoretical simulation to model the interface and microstructural-compositional analyses that confirm our theoretical predictions and allow us to visualize the precise location and constitution of various interfacial components. This work provides new science related to the interfacial stability of Si-based materials while granting positive exposure to ionic liquid electrochemistry.

Journal ArticleDOI
Jiayin Hu1, Jun Ma1, Qinggong Zhu1, Zhaofu Zhang1, Congyi Wu1, Buxing Han1 
TL;DR: A reaction mechanism was proposed on the basis of a detailed DFT study which indicates that both the cation and anion of the PIL play key synergistic roles in accelerating the reaction.
Abstract: Protic ionic liquids (PILs), such as 1,8-diazabicyclo[5.4.0]-7-undecenium 2-methylimidazolide [DBUH][MIm], can catalyze the reaction of atmospheric CO2 with a broad range of propargylic amines to form the corresponding 2-oxazolidinones. The products are formed in high yields under mild, metal-free conditions. The cheaper and greener PILs can be easily recycled and reused at least five times without a decrease in the catalytic activity and selectivity. A reaction mechanism was proposed on the basis of a detailed DFT study which indicates that both the cation and anion of the PIL play key synergistic roles in accelerating the reaction.

Journal ArticleDOI
TL;DR: Self-diffusivities as a function of temperature were computed for 29 different ionic liquids covering a wide variety of cation and anion classes and strongly suggest that the dynamics of ILs are governed by a universal IP or IC forming and breaking mechanism.
Abstract: Self-diffusivities as a function of temperature were computed for 29 different ionic liquids (ILs) covering a wide variety of cation and anion classes. Ideal ionic conductivities (σNE) were estimated from the self-diffusivities via the Nernst–Einstein relation. The ion pair (IP) lifetimes (τIP) and ion cage (IC) lifetimes (τIC) of each IL were also computed. A linear relationship between the calculated self-diffusivities and the inverse of IP or IC lifetimes was observed. A similar inverse linear relationship was also observed for ideal ionic conductivity. These relationships were found to be independent of temperature and the nature of the IL. These observations connect macroscopic dynamic properties with local atomic-level motions and strongly suggest that the dynamics of ILs are governed by a universal IP or IC forming and breaking mechanism. Thus, in order to design an ionic liquid with enhanced dynamics, one should consider how to minimize IP or IC lifetimes.

Journal ArticleDOI
TL;DR: In this paper, a meso-macroporous hierarchical poly(ionic liquid)s (MPILs) with extremely high ionic site densities and tunable pore structures were ionothermally synthesized through the free radical self-polymerization of a newly designed rigid bis-vinylimidazolium salt monomer.
Abstract: Meso-macroporous hierarchical poly(ionic liquid)s (MPILs) with extremely high ionic site densities and tunable pore structures were ionothermally synthesized through the free radical self-polymerization of our newly designed rigid bis-vinylimidazolium salt monomer. The synthesis avoided the use of any templates, gave a high yield (>99%) and allowed recycling of the IL solvent; thus it is facile, atom-efficient, environmentally friendly and sustainable. The synthesized MPILs possessed distinctive features of polycation matrices, abundant halogen anions, and large surface areas. They not only presented enhanced CO2 capture, but led to breakthroughs in the heterogeneous catalytic conversion of CO2 into cyclic carbonates: (1) unprecedented high activity at atmospheric pressure and low temperature; (2) good substrate compatibility, even being active towards the extremely inert aliphatic long carbon-chain alkyl epoxides. This result renders the first occasion of a metal–solvent–additive free recyclable heterogeneous cycloaddition of CO2 at such mild conditions.

Journal ArticleDOI
TL;DR: The quantitative results are used to propose a general model of long-range electrostatic screening in ionic liquids, where thermally activated charge fluctuations, either free ions or correlated domains (quasiparticles), take on the role of ions in traditional dilute electrolyte solutions.
Abstract: Electrolyte solutions with high concentrations of ions are prevalent in biological systems and energy storage technologies. Nevertheless, the high interaction free energy and long-range nature of electrostatic interactions makes the development of a general conceptual picture of concentrated electrolytes a significant challenge. In this work, we study ionic liquids, single-component liquids composed solely of ions, in an attempt to provide a novel perspective on electrostatic screening in very high concentration (nonideal) electrolytes. We use temperature-dependent surface force measurements to demonstrate that the long-range, exponentially decaying diffuse double-layer forces observed across ionic liquids exhibit a pronounced temperature dependence: Increasing the temperature decreases the measured exponential (Debye) decay length, implying an increase in the thermally driven effective free-ion concentration in the bulk ionic liquids. We use our quantitative results to propose a general model of long-range electrostatic screening in ionic liquids, where thermally activated charge fluctuations, either free ions or correlated domains (quasiparticles), take on the role of ions in traditional dilute electrolyte solutions. This picture represents a crucial step toward resolving several inconsistencies surrounding electrostatic screening and charge transport in ionic liquids that have impeded progress within the interdisciplinary ionic liquids community. More broadly, our work provides a previously unidentified way of envisioning highly concentrated electrolytes, with implications for diverse areas of inquiry, ranging from designing electrochemical devices to rationalizing electrostatic interactions in biological systems.

Journal ArticleDOI
TL;DR: In this paper, a new lithium-ether-derived chelate ionic liquid is synthesized to serve as an electrolyte for the Li-O2 battery that is stable to metallic lithium, and whose ethereal framework is much more inherently stable to superoxide-initiated hydrogen abstraction than the simple glyme, dimethoxyethane.
Abstract: A new lithium-ether-derived chelate ionic liquid is synthesized to serve as an electrolyte for the Li-O2 battery that is stable to metallic lithium, and whose ethereal framework is much more inherently stable to superoxide-initiated hydrogen abstraction than the simple glyme, dimethoxyethane (DME). Reactions of chemically generated superoxide with this electrolyte show that virtually no decomposition products such as lithium formate are generated. When the electrolyte is employed in a Li-O2 battery, a ten-fold decrease in CO2 evolution is evident on charge by comparison to DME and greatly enhanced cycling stability is observed with TiC as a cathode support. A mechanism is proposed to account for the lowered reactivity, offering new insight into the stability of organic electrolytes in Li-O2 batteries. This approach for electrolyte design is presented here for the first time, and it can be extended to other organic systems to provide a platform for the design of advanced electrolyte systems.

Journal ArticleDOI
TL;DR: In this paper, a new recycling process for lamp phosphor waste is proposed based on the use of the functionalized ionic liquid betainium bis(trifluoromethylsulfonyl)imide, [Hbet][Tf2N].

Journal ArticleDOI
TL;DR: In this paper, an interesting interaction between oxidized multiwalled carbon nanotubes (oxi-MWCNTs), tetra n-heptylammonium bromide (ionic liquid) and total chromium ((Cr(VI)/Cr(III)) was reported.
Abstract: We report an interesting interaction between oxidized multiwalled carbon nanotubes (oxi-MWCNTs), tetra n-heptylammonium bromide (ionic liquid) and total chromium ((Cr(VI)/Cr(III)) in this study. The interaction between the IL and oxidized MWCNTs primarily involves electrostatic affinity between the quaternary ammonium cation, and surface carboxyl and hydroxyl groups in oxi-MWCNTs. The IL-oxi-MWCNT adsorbent acts as a host in welcoming the incoming guest hydrochromate anions and several interesting interactions such as cation–π interactions, electrostatic interactions as well as anion–π interactions could be conceptualized in this process. The abundant oxygen-containing functional groups on the surfaces of oxi-MWCNTs play an important role in Cr(VI)/Cr(III) sorption. Characterization of the adsorbent was performed using various characterization techniques such as cross polarization magic angle spinning nuclear magnetic resonance (13CPMAS-NMR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), powder-X-ray diffraction (Powder-XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy analysis (TEM), Brunauer–Emmett–Teller (BET) isotherm studies, scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The capability of inductively coupled plasma mass spectrometry (ICP-MS) for Cr(VI) adsorption was extensively studied under different optimal parameters and the maximum adsorption capacity was found to be 85.83 mg g−1 from a nonlinear Langmuir isotherm model. A kinetic study confirms a pseudo second order model and the process could be upgraded by column studies to a sample volume of 2000 mL. Effective regeneration of the adsorbent could be accomplished with sodium hydroxide and the potential of this novel adsorbent has been examined in the removal of Cr(VI)/Cr(III) from aqueous solutions.

Journal ArticleDOI
TL;DR: In this paper, a series of free radical random copolymerizations between N-isopropylacrylamide (NIPAM) and various imidazolium based ionic liquids (ILs) were conducted.

Journal ArticleDOI
Jing Zhang1, Huijie Feng1, Jiaqin Yang1, Qing Qin1, Hongmin Fan1, Caiying Wei1, Wenjun Zheng1 
TL;DR: The CuS microspheres showed enhanced electrochemical performance and high stability for the application in supercapacitors due to intriguing structural design and large specific surface area.
Abstract: It is meaningful to exploit copper sulfide materials with desired structure as well as potential application due to their cheapness and low toxicity. A low-temperature and facile solvothermal method for preparing three-dimensional (3D) hierarchical covellite (CuS) microspheres from an ionic liquid precursor [Bmim]2Cu2Cl6 (Bmim = 1-butyl-3-methylimidazolium) is reported. The formation of CuS nanostructures was achieved by decomposition of intermediate complex Cu(Tu)3Cl (thiourea = Tu), which produced CuS microspheres with diameters of 2.5-4 μm assembled by nanosheets with thicknesses of 10-15 nm. The ionic liquid, as an "all-in-one" medium, played a key role for the fabrication and self-assembly of CuS nanosheets. The alkylimidazolium rings ([Bmim](+)) were found to adsorb onto the (001) facets of CuS crystals, which inhibited the crystal growth along the [001] direction, while the alkyl chain had influence on the assembly of CuS nanosheets. The CuS microspheres showed enhanced electrochemical performance and high stability for the application in supercapacitors due to intriguing structural design and large specific surface area. When this well-defined CuS electrode was assembled into an asymmetric supercapacitor (ASC) with an activated carbon (AC) electrode, the CuS//AC-ASC demonstrated good cycle performance (∼88% capacitance after 4000 cycles) and high energy density (15.06 W h kg(-1) at a power density of 392.9 W kg(-1)). This work provides new insights into the use of copper sulfide electrode materials for asymmetric supercapacitors and other electrochemical devices.

Journal ArticleDOI
TL;DR: The application of nuclear magnetic resonance spectroscopy is demonstrated to study the structure and dynamics of ionic liquids confined in porous carbon electrodes and finds that adsorption and desorption of anions surprisingly plays a more dominant role than that of the cations.
Abstract: Ionic liquids are emerging as promising new electrolytes for supercapacitors While their higher operating voltages allow the storage of more energy than organic electrolytes, they cannot currently compete in terms of power performance More fundamental studies of the mechanism and dynamics of charge storage are required to facilitate the development and application of these materials Here we demonstrate the application of nuclear magnetic resonance spectroscopy to study the structure and dynamics of ionic liquids confined in porous carbon electrodes The measurements reveal that ionic liquids spontaneously wet the carbon micropores in the absence of any applied potential and that on application of a potential supercapacitor charging takes place by adsorption of counterions and desorption of co-ions from the pores We find that adsorption and desorption of anions surprisingly plays a more dominant role than that of the cations Having elucidated the charging mechanism, we go on to study the factors that affect the rate of ionic diffusion in the carbon micropores in an effort to understand supercapacitor charging dynamics We show that the line shape of the resonance arising from adsorbed ions is a sensitive probe of their effective diffusion rate, which is found to depend on the ionic liquid studied, as well as the presence of any solvent additives Taken as whole, our NMR measurements allow us to rationalize the power performances of different electrolytes in supercapacitors

Journal ArticleDOI
TL;DR: In this paper, a procedure for the efficient extraction and separation of rare earths and other valuable elements from used NdFeB permanent magnets is presented, where an iron free leachate is prepared from an used magnet using nitric acid.

Journal ArticleDOI
TL;DR: In this article, an aluminum-sulfur battery comprised of a composite sulfur cathode, aluminum anode and an ionic liquid electrolyte of AlCl3/1-ethyl-3methylimidazolium chloride is described.

Journal ArticleDOI
TL;DR: Hydrophobic magnetic ionic liquids (MILs) were synthesized and employed as solvents for the rapid and efficient extraction of DNA from aqueous solution, demonstrating the feasibility of MIL-based DNA sample preparation prior to downstream analysis.
Abstract: DNA extraction represents a significant bottleneck in nucleic acid analysis. In this study, hydrophobic magnetic ionic liquids (MILs) were synthesized and employed as solvents for the rapid and efficient extraction of DNA from aqueous solution. The DNA-enriched microdroplets were manipulated by application of a magnetic field. The three MILs examined in this study exhibited unique DNA extraction capabilities when applied toward a variety of DNA samples and matrices. High extraction efficiencies were obtained for smaller single-stranded and double-stranded DNA using the benzyltrioctylammonium bromotrichloroferrate(III) ([(C8)3BnN+][FeCl3Br–]) MIL, while the dicationic 1,12-di(3-hexadecylbenzimidazolium)dodecane bis[(trifluoromethyl)sulfonyl]imide bromotrichloroferrate(III) ([(C16BnIM)2C122+][NTf2–, FeCl3Br–]) MIL produced higher extraction efficiencies for larger DNA molecules. The MIL-based method was also employed for the extraction of DNA from a complex matrix containing albumin, revealing a competitive...


Journal ArticleDOI
TL;DR: In this article, the authors summarized rapidly growing studies on the design of thermoresponsive PIL systems with water or organic solvents, and some of the starting IL monomers that show thermore-sponsive phase behaviour were found to maintain their thermore sponsoriveness even after the polymerization.

Journal ArticleDOI
TL;DR: A comprehensive study of ionic liquid mixtures reveals a remarkable adhesion to ideal mixing laws, with some consistent exceptions.
Abstract: Ionic liquids have earned the reputation of being ‘designer solvents’ due to the wide range of accessible properties and the degree of fine-tuning afforded by varying the constituent ions. Mixtures of ionic liquids offer the opportunity for further fine-tuning of properties. A broad selection of common ionic liquid cations and anions are employed to create a sample of binary and reciprocal binary ionic liquid mixtures, which are analysed and described in this paper. Physical properties such as the conductivity, viscosity, density and phase behaviour (glass transition temperatures) are examined. In addition, thermal stabilities of the mixtures are evaluated. The physical properties examined for these formulations are found to generally adhere remarkably closely to ideal mixing laws, with a few consistent exceptions, allowing for the facile prediction and control of properties of ionic liquid mixtures.

Journal ArticleDOI
TL;DR: In this paper, 1-alkyl-3-methylimidazolium ionic liquids (ILs) were used for catalyzing the formylation of amines using CO2 and phenylsilane at room temperature, producing the corresponding formylated products in excellent yields under the metal-free condition.
Abstract: The CO2-involved synthesis of chemicals is of significance. In this work, we found that 1-alkyl-3-methylimidazolium ionic liquids (ILs) had high efficiency for catalyzing the formylation of amines using CO2 and phenylsilane at room temperature, producing the corresponding formylated products in excellent yields under the metal-free condition. The ILs acted as bifunctional catalysts, which activated the Si-H bond of phenylsilane to react with CO2 to form the formoxysilane intermediate and simultaneously activated the amine substrate through the hydrogen bond. Moreover, the imidazolium cation and the anions of the ILs showed an excellent synergistic effect on catalyzing the formylation of amines.