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The glass transition dynamics and conductivity relaxation are studied for a series of non-stoichiometric protic ionic liquids (PILs) based on 2-aminoethyl hydrogen sulfate and triflic acid with varying molar ratios (denoted as AT-55, AT-46, AT-37, AT-28, and AT-19) by broadband dielectric spectroscopy in a wide frequency (10−1–107 Hz) and temperature range (173–353 K). The results indicate that the addition of acid lowers the glass transition temperature, as confirmed by the activation energy fine structure analysis and a crossover in the conductivity relaxation time. Notably, samples with higher acid content deliver markedly increased conductivity. In addition, detailed analysis of the permittivity and modulus spectra reveals enhanced decoupling between the structural (α-process) and conductivity relaxation in samples with a higher acid content. Remarkably, nano-phase separation in AT-28 and AT-19 samples is observed, resulting in a second glass transition temperature indicating a more mobile phase. Based on the above-mentioned findings, we infer that increased acid content disrupts strong ionic interactions within the IL fraction, resulting in a decrease in the glass transition temperature and leading to nano-phase separation into distinct acid-rich and IL-rich phases with varying Tg values. This phase separation alters the long-range ionic pathways, shifting from being solely governed by IL cluster dynamics to a scenario where charge transport becomes largely decoupled from the dynamics of IL-rich clusters. Hence, modulating the stoichiometry of PILs appears a promising approach to enhance the conductivity together with widening the usable temperature range for applications. [ABSTRACT FROM AUTHOR]

All-inorganic perovskite CsPbBr3 nanocrystals (NCs) display high photoluminescence quantum yield and narrow emission, which show great potential application in optoelectronic devices. However, the poor environment stability of NCs will hinder their practical application. Herein, a series of ionic liquids with different anions (BF4−, Br−, and NO3−) were used as a sole capping ligand to synthesize NCs. Among the three samples, 1-hexadecyl-3-methylimidazolium tetrafluoroborate ([C16MIM]BF4) capped NCs have the highest stability in light, thermal, and water, possibly attributing to the in situ passivation of bromine vacancy via pseudohalogen BF4− and tight binding of ionic liquid ligands and lead atoms. In addition, green-emission [C16MIM]BF4 NCs were used to assemble a white light-emitting diode device, and it possessed a wide National Television System Committee color gamut of 124.5% and a stable emission peak at high driving currents of 380 mA. This work paves the way for resurfacing perovskite NCs with ultrahigh stability, thereby driving the perovskite NC display industry closer to real-world application. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are a unique class of solvents with potential applications in advanced separation technologies relevant to the nuclear industry. ILs are salts with low melting points and a wide range of tunable physical properties, such as viscosity, hydrophobiciy, conductivity, and liquidus range. ILs have negligible vapor pressure, are often non-flammable, and can have high thermal stability and a wide electrochemical window, making them attractive for use in separations processes relevant to the nuclear industry. Metal salts generally have a low solubility in ILs; however, by incorporating new functional groups into the IL cation or anion that promote complexation with the metal, the solubility can be greatly increased. One such task-specific ionic liquid (TSIL) is 1-carboxy-N, N, N-trimethylglycine bis(trifluoromethylsulfonyl)imide ([Hbet][Tf2N]) [Nockemann et al., J. Phys. Chem. B 110, 20978–20992 (2006)]. Water, which is detrimental for electrochemical separations, is a common impurity in ILs and can coordinate with actinyl cations, particularly in ILs containing only weakly coordinating components. Understanding the behavior of actinides in TSIL/water mixtures on a molecular level is vital for designing improved separations processes. Classical molecular dynamics simulations of uranyl(VI) and plutonyl(VI) in 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][Tf2N]) with deprotonated Hbet (betaine) and water have been performed to understand the coordination and dynamics of the actinyl cations. We find that betaine is a much stronger ligand than water and prefers to coordinate the metal in a bidentate manner. Potential of mean force simulations yield a relative free energy for betaine coordination of approximately −120 to −90 kJ/mol in mixtures with water. As the amount of betaine coordinated to the actinide increases, the diffusion coefficient of the actinyl cation decreases. Moreover, the betaine ligand is able to bridge between two metal centers, resulting in dimeric complexes with actinide–actinide distances of ∼5 Å. Potential of mean force simulations show that these structures are stable, with relative free energies of up to −40 kJ/mol. The crystal structure for [(UO2)2(bet)6(H2O)2][Tf2N]4 shows that the betaine bridges between two uranium atoms to form dimeric complexes similar to those found in our simulations [Nockemann et al. Inorg. Chem. 49, 3351–33601 (2010)]. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents have recently gained significant attention as versatile and inexpensive materials with many desirable properties and a wide range of applications. In particular, their characteristics, similar to those of ionic liquids, make them a promising class of liquid electrolytes for electrochemical applications. In this study, we utilized a local equivariant neural network interatomic potential model to study a series of deep eutectic electrolytes based on lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) using molecular dynamics (MD) simulations. The use of equivariant features combined with strict locality results in highly accurate, data-efficient, and scalable interatomic potentials, enabling large-scale MD simulations of these liquids with first-principles accuracy. Comparing the structure of the liquids to the reported results from classical force field (FF) simulations indicates that ion–ion interactions are not accurately characterized by FFs. Furthermore, close contacts between lithium ions, bridged by oxygen atoms of two amide molecules, are observed. The computed cationic transport numbers (t+) and the estimated ratios of Li+–amide lifetime (τLi–amide) to the amide's rotational relaxation time (τR), combined with the ionic conductivity trend, suggest a more structural Li+ transport mechanism in the LiTFSI:urea mixture through the exchange of amide molecules. However, a vehicular mechanism could have a larger contribution to Li+ ion transport in the LiTFSI:N-methylacetamide electrolyte. Moreover, comparable diffusivities of Li+ cation and TFSI− anion and a τLi–amide/τR close to unity indicate that vehicular and solvent-exchange mechanisms have rather equal contributions to Li+ ion transport in the LiTFSI:acetamide system. [ABSTRACT FROM AUTHOR]

A porous electrospray ion source was tested with three ionic liquids in order to investigate the effects of ionic liquid properties on the sizes of ion clusters emitted by purely ionic electrospray sources. Two of the ionic liquids, bis(1-ethyl-3-methylimidazolium) tetrathiocyanatocobaltate and 1,6-bis(3-methylimidazolium-1-yl)hexane bis(trifluoromethylsulfonyl)amide, were selected due to them having a dication or dianion, which were termed multiply charged ionic liquids due to them containing anions or cations with more than one charge within them. These were selected in order to investigate ionic clustering within electrospray ion emission and were compared against one of the most common ionic liquids, EMI-BF4. The current–voltage data showed that EMI-BF4 emitted similar levels of current to bis(1-ethyl-3-methylimidazolium) tetrathiocyanatocobaltate, even though the latter liquid had significantly lower conductivity and higher viscosity, suggesting an improvement in current speculated to be due to the extra charges contained by the ions. Time-of-flight and retarding potential analysis data are provided, showing all three liquids emitting ions comprising of monomers, dimers, trimers, and quadramers, with some of the 1,6-bis(3-methylimidazolium-1-yl)hexane bis(trifluoromethylsulfonyl)amide data showing heavier species emission. The data also suggested that the multiply charged ionic liquids produced ions that have two anions or cations attached, termed "double ions," with these ions not been previously reported using porous electrospray sources. Furthermore, it was found that the dimers emitted by both of the multiply charged ionic liquids seemed to be more stable than EMI-BF4 dimers, providing insight into ion cluster formation. [ABSTRACT FROM AUTHOR]

We employ polymer integral equation theory to study a simplified model of semiflexible polymerized ionic liquids (PolyILs) that interact via hard core repulsions and short range screened Coulomb interactions. The multi-scale structure in real and Fourier space of PolyILs (ions chosen to mimic Li, Na, K, Br, PF6, and TFSI) are determined as a function of melt density, Coulomb interaction strength, and ion size. Comparisons with a homopolymer melt, a neutral polymer–solvent-like athermal mixture, and an atomic ionic liquid are carried out to elucidate the distinct manner that ions mediate changes of polymer packing, the role of excluded volume effects, and the influence of chain connectivity, respectively. The effect of Coulomb strength depends in a rich manner on ion size and density, reflecting the interplay of steric packing, ion adsorption, and charge layering. Ion-mediated bridging of monomers is found, which intensifies for larger ions. Intermediate range charge layering correlations are characterized by a many-body screening length that grows with PolyIL density, cooling, and Coulomb strength, in disagreement with Debye–Hückel theory, but in accord with experiments. Qualitative differences in the collective structure, including an ion-size-dependent bifurcation of the polymer structure factor peak and pair correlation function, are predicted. The monomer cage order parameter increases significantly, but its collective ion counterpart decreases, as ions become smaller. Such behaviors allow one to categorize PolyILs into two broad classes of small and large ions. Dynamical implications of the predicted structural results are qualitatively discussed. [ABSTRACT FROM AUTHOR]

A non-polarizable force field for lithium (Li+) and bis(trifluoromethanesulfonyl)imide (TFSI−) ions solvated in diglyme at around 0.2 mol fraction salt concentration was developed based on ab initio molecular dynamics (AIMD) simulations and a modified polymer consistent force field model. A force–torque matching based scheme, in conjunction with a genetic algorithm, was used to determine the Lennard-Jones (LJ) parameters of the ion–ion and ion–solvent interactions. This force field includes a partial charge scaling factor and a scaling factor for the 1–4 interactions. The resulting force field successfully reproduces the radial distribution function of the AIMD simulations and shows better agreement compared to the unmodified force field. The new force field was then used to simulate salt solutions with glymes of increasing chain lengths and different salt concentrations. The comparison of the MD simulations, using the new force field, with experimental data at different salt concentrations and AIMD simulations on equimolar concentrations of the triglyme system demonstrates the transferability of the force field parameters to longer glymes and higher salt concentrations. Furthermore, the force field appears to reproduce the features of the experimental x-ray structure factors, suggesting accuracy beyond the first solvation shell, for equimolar salt solutions using both triglyme and tetraglyme as the solvent. Overall, the new force field was found to accurately reproduce the molecular descriptions of LiTFSI-glyme systems not only at various salt concentrations but also with glymes of different chain lengths. Thus, the new force field provides a useful and accurate tool to perform in silico studies of this family of systems at the atomistic level. [ABSTRACT FROM AUTHOR]

We have used surface plasmon resonant metal gratings to induce and probe the dielectric response (i.e., electro-optic modulation) of ionic liquids (ILs) at electrode interfaces. Here, the cross-plane electric field at the electrode surface modulates the refractive index of the IL due to the Pockels effect. This is observed as a shift in the resonant angle of the grating (i.e., Δϕ), which can be related to the change in the local index of refraction of the electrolyte (i.e., Δnlocal). The reflection modulation of the IL is compared against a polar (D2O) and a non-polar solvent (benzene) to confirm the electro-optic origin of resonance shift. The electrostatic accumulation of ions from the IL induces local index changes to the gratings over the extent of electrical double layer (EDL) thickness. Finite difference time domain simulations are used to relate the observed shifts in the plasmon resonance and change in reflection to the change in the local index of refraction of the electrolyte and the thickness of the EDL. Simultaneously using the wavelength and intensity shift of the resonance enables us to determine both the effective thickness and Δn of the double layer. We believe that this technique can be used more broadly, allowing the dynamics associated with the potential-induced ordering and rearrangement of ionic species in electrode–solution interfaces. [ABSTRACT FROM AUTHOR]

Room temperature ionic liquids (RTILs) are molten salts consisting entirely of ions and have over the past decades gained increased interest due to their high potential in applications. These structurally complex systems often display multiple relaxation modes in the response functions at lower frequencies, hinting to complex underlying mechanisms. While the existence of these multimodal spectra in the shear mechanical, dielectric, and light scattering response of RTILs has been confirmed multiple times, controversy still surrounds the origin. This paper, therefore, aims to provide additional insights into the multimodal spectra seen in RTILs by presenting new shear mechanical results on seven different RTILs: Pyr1n-TFSI with n = 4, 6, and 8; Pyr18-TFSI mixed with Li-TFSI in two high concentrations; and Cn-mim-BF4 with n = 3 and 8. Dynamic depolarized light scattering was also measured on one of the Pyr18-TFSI Li-salt mixtures. These specific cases were analyzed in detail and put into a bigger perspective together with an overview of the literature. Recent literature offers two specific explanations for the origin of the multimodal shear mechanical spectra: (1) cation–anion time scale separation or (2) combined cation–anion relaxation in addition to a dynamic signal from mesoscale aggregates at lower frequencies. However, neither of these two pictures can consistently explain all the results on different ionic liquids. Instead, we conclude that the origin of the multimodal spectrum is system specific. This underlines the complexity of this class of liquids and shows that great care must be taken when making general conclusions based on specific cases. [ABSTRACT FROM AUTHOR]

Recently, we reported the discovery of a novel endoglucanase of the glycoside hydrolase family 12 (GH12), designated IfCelS12A, from the haloalkaliphilic anaerobic bacterium Iocasia fonsfrigidae strain SP3-1, which was isolated from a hypersaline pond in the Samut Sakhon province of Thailand (ca. 2017). IfCelS12A exhibits high substrate specificity on carboxymethyl cellulose and amorphous cellulose but low substrate specificity on b-1,3;1,4-glucan. Unlike some endoglucanases of the GH12 family, IfCelS12A does not exhibit hydrolytic activity on crystalline cellulose (i.e., Avicel™). High-Pressure Liquid Chromatography (HPLC) and Thin Layer Chromatography (TLC) analyses of products resulting from IfCelS12-mediated hydrolysis indicate mode of action for this enzyme. Notably, IfCelS12A preferentially hydrolyzes cellotetraoses, cellopentaoses, and cellohexaoses with negligible activity on cellobiose or cellotriose. Kinetic analysis with cellopentaose and barely b-D-glucan as cellulosic substrates were conducted. On cellopentaose, IfCelS12A demonstrates a 16-fold increase in activity (KM = 0.27 mM; kcat = 0.36 s-1; kcat/KM = 1.34 mM-1 s-1) compared to the enzymatic hydrolysis of barley b-D-glucan (KM: 0.04 mM, kcat: 0.51 s-1, kcat/KM = 0.08 mM-1 s-1). Moreover, IfCelS12A enzymatic efficacy is stable in hypersaline sodium chlorids (NaCl) solutions (up to 10% NaCl). Specifically, IfCel12A retains notable activity after 24 h at 2M NaCl (10% saline solution). IfCelS12A used as a cocktail component with other cellulolytic enzymes and in conjunction with mobile sequestration platform technology offers additional options for deconstruction of ionic liquid-pretreated cellulosic feedstock. KEY POINTS: • IfCelS12A from an anaerobic alkaliphile Iocasia fronsfrigidae shows salt tolerance • IfCelS12A in cocktails with other enzymes efficiently degrades cellulosic biomass • IfCelS12A used with mobile enzyme sequestration platforms enhances hydrolysis.

Ionic liquid electrospray thrusters represent an alternative propulsion method for spacecraft to conventional plasma propulsion because they do not require plasma generation, which significantly increases the thrust efficiency. The porous emitter thruster has the advantages of simple propellant feeding and multi-site emissions, which miniaturize the thruster size and increase thrust. However, the multi-scale nature, that is, nano- to micrometer-sized menisci on the millimeter-size porous needle tip, makes modeling multi-site emissions difficult, and direct observation is also challenging. This paper proposes a simple model for multi-site emissions, which assumes that the ionic conductivity or ion transport in the porous media determines the ion-emission current. The conductivity was evaluated by comparing the experimental and numerical data based on the model. The results suggest that the ionic conductivity of the porous emitter is suppressed by the ion–pore wall friction stress. Additionally, the model indicates that the emission area expansion on the porous emitter creates the unique curve shape of the current vs voltage characteristics for multi-site emissions. [ABSTRACT FROM AUTHOR]

Redox potentials depend on the nature of the solvent/electrolyte through the solvation energies of the ionic solute species. For concentrated electrolytes, ion solvation may deviate significantly from the Born model predictions due to ion pairing and correlation effects. Recently, Ghorai and Matyushov [J. Phys. Chem. B 124, 3754–3769 (2020)] predicted, on the basis of linear response theory, an anomalous trend in the solvation energies of room temperature ionic liquids, with deviations of hundreds of kJ/mol from the Born model for certain size solutes/ions. In this work, we computationally evaluate ionic solvation energies in the prototypical ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM/BF4), to further explore this behavior and benchmark several of the approximations utilized in the solvation energy predictions. For comparison, we additionally compute solvation energies within acetonitrile and molten NaCl salt to illustrate the limiting behavior of purely dipolar and ionic solvents. We find that the overscreening effect, which results from the inherent charge oscillations of the ionic liquid, is substantially reduced in magnitude due to screening from the dipoles of the molecular ions. Therefore, for the molten NaCl salt, for which the ions do not have permanent dipoles, modulation of ionic solvation energies from the overscreening effect is most significant. The conclusion is that ionic liquids do indeed exhibit unique solvation behavior due to peak(s) in the electrical susceptibility caused by the ion shell structure; redox potential shifts for BMIM/BF4 are of more modest order ∼0.1 V, but may be larger for other ionic liquids that approach molten salt behavior. [ABSTRACT FROM AUTHOR]

Crystal polymorphism of complex liquids plays a crucial role in industrial crystallization, food technology, pharmaceuticals, and materials engineering. However, the experimental identification of unknown crystal structures can be challenging, particularly for high-viscosity complex liquids, such as ionic liquids (ILs). In this study, we performed a molecular dynamics simulation coupled with metadynamics to investigate an imidazolium IL (1-alkyl-3-methylimidazolium hexafluorophosphates). The simulation employed two distinct radial-distribution functions, represented by Gaussian window functions as collective variables, and revealed at least two crystal-like phases distinct from the known α and β crystal phases typically formed by this IL. Additionally, the simulation unveiled a unique phase characterized by the ordered spatial arrangement of anion aggregations. These crystal-like and unique phases emerged regardless of the potential used. The simulation methodology presented here is broadly applicable for exploring unknown phases in complex systems and contributes to the design of functional materials, such as porous ILs for gas molecule capture and separation. [ABSTRACT FROM AUTHOR]

In this work, we propose and validate a generalization of the Helmholtz model that can account for both "bell-shaped" and "camel-shaped" differential capacitance profiles of concentrated electrolytes, the latter being characteristic of ionic liquids. The generalization is based on introducing voltage dependence of both the dielectric constant "ϵr(V)" and thickness "L(V)" of the inner Helmholtz layer, as validated by molecular dynamics (MD) simulations. We utilize MD simulations to study the capacitance profiles of three different electrochemical interfaces: (1) graphite/[BMIm+][ BF 4 − ] ionic liquid interface; (2) Au(100)/[BMIm+][ BF 4 − ] ionic liquid interface; (3) Au(100)/1M [Na+][Cl−] aqueous interface. We compute the voltage dependence of ϵr(V) and L(V) and demonstrate that the generalized Helmholtz model qualitatively describes both camel-shaped and bell-shaped differential capacitance profiles of ionic liquids and concentrated aqueous electrolytes (in lieu of specific ion adsorption). In particular, the camel-shaped capacitance profile that is characteristic of ionic liquid electrolytes arises simply from combination of the voltage-dependent trends of ϵr(V) and L(V). Furthermore, explicit analysis of the inner layer charge density for both concentrated aqueous and ionic liquid double layers reveal similarities, with these charge distributions typically exhibiting a dipolar region closest to the electrode followed by a monopolar peak at larger distances. It is appealing that a generalized Helmholtz model can provide a unified description of the inner layer structure and capacitance profile for seemingly disparate aqueous and ionic liquid electrolytes. [ABSTRACT FROM AUTHOR]

This work employs a combination of density functional theory-infrared (IR), conductor-like screening model for real solvents (COSMO-RS), and molecular dynamic (MD) methods to investigate the impact of hydroxyl functional groups on CO2 capture within dicationic ionic liquids (DILs). The COSMO-RS reveals that hydroxyl groups in DILs reduce the macroscopic solubility of CO2 but improve the selectivity of CO2 over CO, H2, and CH4 gases. Quantum methods in the gas phase and MD simulations in the liquid phase were conducted to delve deeper into the underlying mechanisms. The IR spectrum analysis confirms red shifts in CO2's asymmetric stretching mode and blue shifts in the CR–HR bond of the dication, indicating CO2–DIL interactions and the weakening of the anion–cation interactions caused by the presence of CO2. The results show that the positioning of anions around hydroxyl groups and HR atoms in rings inhibits the proximity of CO2 molecules, causing the hydrogen atoms within methylene groups to accumulate CO2. van der Waals forces were found to dominate the interaction between ions and CO2. The addition of hydroxyl groups strengthens the electrostatic interactions and hydrogen bonds between dications and anions. The stronger interaction energy between ions in [C5(mim)2-(C2)2(OH)2][NTf2]2 limits the displacement of CO2 molecules within this DIL compared to [C5(mim)2-(C4)2][NTf2]2. Compared to [C5(mim)2-(C4)2][NTf2]2, [C5(mim)2-(C2)2(OH)2][NTf2]2 exhibits stronger ion–ion interactions, higher density, and reduced free volume, resulting in a reduction in CO2 capture. These results provide significant insights into the intermolecular interactions and vibrational properties of CO2 in DIL complexes, emphasizing their significance in developing efficient and sustainable strategies for CO2 capture. [ABSTRACT FROM AUTHOR]

Visualizing the network of a solvent-swollen polymer gel remains problematic. To address this challenge, open transmission electron microscopy (TEM) was applied to thin gel films permeated by a nonvolatile ionic liquid. The targeted physical gels were prepared by cooling concentrated solutions of poly(ethylene glycol) in 1-ethyl-3-methyl imidazolium ethyl sulfate [EMIM][EtSO4]. During the cooling, gelation occurred by a frustrated crystallization of the dissolved polymer, leading to a percolated, solvent-permeated semicrystalline network in which nanoscale polymer crystals acted as crosslinks. Crystalline features ranging from ~5 to ~200 nm were observed, with the visible network strands dominantly consisting of long curvilinear crystallites of ~15–20 nm diameter. Nascent spherulites irregularly decorated the network, creating a complex structural hierarchy that complicated analyses. Lacking diffraction contrast, TEM did not visualize the many disordered, fully solvated PEG chains present in the voids between crystals. Recognizing that a network's three dimensionality is ambiguous when assessed through two-dimensional microscopy projections, a small gel region was studied by TEM tomography, revealing a nearly isotropic three-dimensional arrangement of the curvilinear crystallites, which displayed remarkably uniform cylindrical cross sections.

Experimental and theoretical advances for understanding the temperature of maximum density (TMD) of aqueous solutions are outlined. The main equations that relate the TMD behavior to key thermodynamic properties are stated. The experimental TMD data are classified as a function of the nature of the solute (inorganic electrolytes, non-electrolytes, organic salts and ionic liquids, and amino acids and proteins). In addition, the experimental results that explore the effect of pressure are detailed. These experimental data are rationalized by making use of qualitative and semi-quantitative arguments based on the thermodynamics of aqueous systems. The main theoretical and simulation advances in TMD for aqueous solutions are also shown—including new calculations in the context of the scaled particle theory—and their ability to reproduce the experimental data is evaluated. Finally, new experiments and theoretical and simulation developments, which could give important insights into the problem of TMD for aqueous solutions, are proposed. [ABSTRACT FROM AUTHOR]

We study a united-atom model of the ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethyl)sulfonylamide to determine to what extent there exist curves in the phase diagram along which the microscopic dynamics are invariant when expressed in dimensionless, or reduced, form. The initial identification of these curves, termed isodynes, is made by noting that contours of reduced shear viscosity and reduced self-diffusion coefficient coincide to a good approximation. Choosing specifically the contours of reduced viscosity as nominal isodynes, further simulations were carried out for state points on these, and other aspects of dynamics were investigated to study their degree of invariance. These include the mean-squared displacement, shear-stress autocorrelation function, and various rotational correlation functions. These were invariant to a good approximation, with the main exception being rotations of the anion about its long axis. The dynamical features that are invariant have in common that they are aspects that would be relevant for a coarse-grained description of the system; specifically, removing the most microscopic degrees of freedom in principle leads to a simplification of the potential energy landscape, which allows for the existence of isodynes. [ABSTRACT FROM AUTHOR]

Recent experimental results have demonstrated that zwitterionic ionogel comprised of polyzwitterion (polyZI)-supported lithium salt-doped ionic liquid exhibits improved conductivities and lithium transference numbers than the salt-doped base ionic liquid electrolyte (ILE). However, the underlying mechanisms of such observations remain unresolved. In this work, we pursued a systematic investigation to understand the impact of the polyZI content and salt concentration on the structural and dynamic properties of the poly(MPC) ionogel of our model polyZI ionogel, poly(2-methacryloyloxyethyl phosphorylcholine) [poly(MPC)] supported LiTFSI/N-butyl-N-methylpyrrolidinium TFSI base ionic liquid electrolyte. Our structural analyses show strong lithium–ZI interaction consistent with the physical network characteristic observed in the experiments. An increase in polyZI content leads to an increased fraction of Li+ ions coordinated with the polyZI. In contrast, an increase in salt concentration leads to a decreased fraction of Li+ ions coordinated with the polyZI. The diffusivities of the mobile ions in the poly(MPC) ionogel were found to be lower than the base ILE in agreement with experiments at T > 300 K. Analysis of ion transport mechanisms shows that lithium ions within the poly(MPC) ionogel travel via a combination of structural, vehicular diffusion, as well as hopping mechanism. Finally, the conductivity trend crossover between the poly(MPC) ionogel and the base ILE was rationalized via a temperature study that showed that the base ILE ions are influenced more by the variation of temperature when compared to the poly(MPC) ions. [ABSTRACT FROM AUTHOR]

Monoolein-based liquid crystal phases are established media that are researched for various biological applications, including drug delivery. While water is the most common solvent for self-assembly, some ionic liquids (ILs) can support lipidic self-assembly. However, currently, there is limited knowledge of IL-lipid phase behavior in ILs. In this study, the lyotropic liquid crystal phase behavior of monoolein was investigated in six protic ILs known to support amphiphile self-assembly, namely ethylammonium nitrate, ethanolammonium nitrate, ethylammonium formate, ethanolammonium formate, ethylammonium acetate, and ethanolammonium acetate. These ILs were selected to identify specific ion effects on monoolein self-assembly, specifically increasing the alkyl chain length of the cation or anion, the presence of a hydroxyl group in the cation, and varying the anion. The lyotropic liquid crystal phases with 20–80 wt. % of monoolein were characterized over a temperature range from 25 to 65 °C using synchrotron small angle x-ray scattering and cross-polarized optical microscopy. These results were used to construct partial phase diagrams of monoolein in each of the six protic ILs, with inverse hexagonal, bicontinuous cubic, and lamellar phases observed. Protic ILs containing the ethylammonium cation led to monoolein forming lamellar and bicontinuous cubic phases, while those containing the ethanolammonium cation formed inverse hexagonal and bicontinuous cubic phases. Protic ILs containing formate and acetate anions favored bicontinuous cubic phases across a broader range of protic IL concentrations than those containing the nitrate anion. [ABSTRACT FROM AUTHOR]

In this study, we extended the optimized potentials for liquid simulation-ionic-liquid virtual site (OPLS-VSIL) force field (FF) to imidazolium-based dicationic ionic liquids (DILs) and evaluated the ability of different OPLS-based FFs (i.e., OPLS-2009IL, 0.8*OPLS-2009IL, and OPLS-VSIL) in predicting different properties of the studied DIL by comparing their results with ab initio molecular dynamics (AIMD) simulation and experimental results. To achieve this purpose, MD simulations with three different OPLS-based FFs as well as AIMD simulation were performed for [C3(mim)2][NTF2]2 DIL and its structural, dynamical, vibrational, and volumetric properties were analyzed. Structural properties of the studied DIL, i.e., radial distribution functions (RDFs), structure factor, and hydrogen-bond network, showed that compared to 0.8*OPLS-2009IL FF, there is a much better agreement between the results of both OPLS-2009IL and OPLS-VSIL FFs with the AIMD simulation. On the other hand, the results of dynamical properties, such as mean square displacements, van Hove correlation functions as well as hydrogen bond, ion pair, and ion cage dynamics, depicted that in both 0.8*OPLS-2009IL and OPLS-VSIL FFs, the dynamics of the system is almost similar, and compared to OPLS-2009IL FF, they have better agreements with experimental results where they exist. So, it can be seen that although reducing the total charge of studied DIL by 20% leads to an increase in the dynamics of the system, the type distribution of partial charges on each atom does not significantly affect the system's dynamics. The calculated infrared (IR) and power spectra showed that the vibrational features of studied DIL in three OPLS-based FFs are mostly the same and reducing total charge and different type distribution of partial charges have no significant effect on the studied system. Furthermore, in volumetric properties, OPLS-VSIL FF shows somehow better agreement with experimental results. Overall, the evaluation of different structural, dynamical, vibrational, and volumetric properties of [C3(mim)2][NTF2]2 DIL shows that the OPLS-VSIL FF may be the best choice among the different studied OPLS FFs. [ABSTRACT FROM AUTHOR]

Electrochemical Double Layer Capacitors (EDLCs) with ionic liquid electrolytes outperform conventional ones using aqueous and organic electrolytes in energy density and safety. However, understanding the electrochemical behaviors of ionic liquid electrolytes under compressive/tensile strain is essential for the design of flexible EDLCs as well as normal EDLCs, which are subject to external forces during assembly. Despite many experimental studies, the compression/stretching effects on the performance of ionic liquid EDLCs remain inconclusive and controversial. In addition, there is hardly any evidence of prior theoretical work done in this area, which makes the literature on this topic scarce. Herein, for the first time, we developed an atomistic model to study the processes underlying the electrochemical behaviors of ionic liquids in an EDLC under strain. Constant potential non-equilibrium molecular dynamics simulations are conducted for EMIM BF4 placed between two graphene walls as electrodes. Compared to zero strain, low compression of the EDLC resulted in compromised performance as the electrode charge density dropped by 29%, and the performance reduction deteriorated significantly with a further increase in compression. In contrast, stretching is found to enhance the performance by increasing the charge storage in the electrodes by 7%. The performance changes with compression and stretching are due to changes in the double-layer structure. In addition, an increase in the value of the applied potential during the application of strain leads to capacity retention with compression revealed by the newly performed simulations. [ABSTRACT FROM AUTHOR]

We present a strategic approach for enhancing the ionic conductivity of block copolymer electrolytes. This was achieved by introducing mixed ionic liquids (ILs) with varying molar ratios, wherein the imidazolium cation was paired with either tetrafluoroborate (BF4) anion or bis(trifluoromethylsulfonyl)imide (TFSI) anion. Two polymer matrices, poly(4-styrenesulfonate)-b-polymethylbutylene (SSMB) and poly(4-styrenesulfonyl (trifluoromethanesulfonyl)imide)-b-polymethylbutylene (STMB), were synthesized for this purpose. All the SSMB and STMB containing mixed ILs showed hexagonal cylindrical structures, but the type of tethered acid group significantly influenced the interfacial properties. STMB electrolytes demonstrated enhanced segregation strength, which was attributed to strengthened Coulomb and hydrogen bonding interactions in the ionic domains, where the ILs were uniformly distributed. In contrast, the SSMB electrolytes exhibited increased concentration fluctuations because the BF4 anions were selectively sequestered at the block interfaces. This resulted in the effective confinement of imidazolium TFSI along the ionic domains, thereby preventing ion trapping in dead zones and facilitating rapid ion diffusion. Consequently, the SSMB electrolytes with mixed ILs demonstrated significantly improved ionic conductivities, surpassing the expected values based on the arithmetic average of the conductivities of each IL, whereas the ionic conductivity of the STMB was aligned with the expected average. The methodology explored in this study holds great promise for the development of solid-state polymer electrolytes. [ABSTRACT FROM AUTHOR]

Highly acidic protic ionic liquids (PILs) are promising materials for potential electrochemical applications due to their high proton conductivity and excellent thermal stability. Still, little is known about the correlation between charge transport and structural dynamics as well as the proton transport mechanism despite the large body of literature on this topic. Here, we have examined the charge transport and structural dynamics by employing broadband dielectric spectroscopy in two highly acidic PILs in their supercooled liquid and glassy states, which included the same anion [TfO]− and different cations, [Tau]+ vs [Ahs]+. Unlike many other ionic liquids, the conductivity relaxation time τe of two studied PILs is substantially faster than the structural relaxation time τα. The decoupling behavior between charge transport and structural dynamics of two materials, which is manifested by a decoupling index Rτ, varies between 0.3 and 2.3 over the temperature range above Tg. Moreover, "Walden" plots of the molar conductivity vs the viscosity qualify both compounds as "Super ILs." All findings support the physical picture of large, polar, and orientationally correlated ion clusters, where the slow α-relaxation can be identified as structural relaxation associated with cooperative reorientations of the cluster macrodipole. In contrast, the shortest timescale for diffusive charge transport, τe, is 1–2 decades shorter than τα, implying that proton hopping is triggered by "single particle" (ions or ion pair) rotations and jumps on a sub-length scale of the cluster size, a dynamics being present even in the glassy state as indicated by a strong β-relaxation. These results demonstrate the practicality of employing highly acidic PILs in electrochemical fields. [ABSTRACT FROM AUTHOR]

Due to the importance of supercapacitors in electronic storage devices, improving their efficiency is one of the topics that has attracted the attention of many researchers. Choosing the proper electrolyte for supercapacitors is one of the most significant factors affecting supercapacitors' performance. In the present paper, we compare liquid electrolytes (ionic liquid electrolytes) and solid electrolytes (polymer electrolytes) by molecular dynamics simulation to summarize their pros and cons. We consider polymer electrolytes in linear and network configurations. The results show that although ionic liquid-based supercapacitors have a larger differential capacitance since they have a smaller operation voltage, the energy stored is less than polymer electrolyte-based supercapacitors. Also, our investigations indicate that polymer electrolyte-based supercapacitors have more mechanical stability. Therefore, they can be considered a very suitable alternative to liquid electrolyte-based supercapacitors since they do not have known liquid electrolyte problems and display better performance. [ABSTRACT FROM AUTHOR]

The use of ionic liquids (ILs) as lubricants or additives has been studied extensively over the past few decades. However, the ILs considered for lubricant applications have been part of a limited structural class of phosphonium- or imidazolium-type compounds. Here, new pyrylium- and pyridinium-based ILs bearing long alkyl chains were prepared and evaluated as friction- and wear-reducing additives in naphthenic greases. The physical properties of the synthetic ILs and additized naphthenic grease were measured. The tribological performance of the greases was measured by using standard benchtop tests. The addition of ILs was detrimental to wear, causing an increase in the amount of material removed by sliding relative to the base greases in most cases. In contrast, the friction performance improved under nearly all conditions tested due to the IL additives. The compatibility of the synthetic ILs with the naphthenic greases and its potential influence upon miscibility and tribological performance are tentatively proposed to be a result of the molecular structure.

Sustainably grown biomass is a promising alternative to produce fuels and chemicals and reduce the dependency on fossil energy sources. However, the efficient conversion of lignocellulosic biomass into biofuels and bioproducts often requires extensive testing of components and reaction conditions used in the pretreatment, saccharification, and bioconversion steps. This restriction can result in a significant and unwieldy number of combinations of biomass types, solvents, microbial strains, and operational parameters that need to be characterized, turning these efforts into a daunting and time-consuming task. Here we developed a high-throughput feedstocks-to-fuels screening platform to address these challenges. The result is a miniaturized semi-automated platform that leverages the capabilities of a solid handling robot, a liquid handling robot, analytical instruments, and a centralized data repository, adapted to operate as an ionic-liquid-based biomass conversion pipeline. The pipeline was tested by using sorghum as feedstock, the biocompatible ionic liquid cholinium phosphate as pretreatment solvent, a "one-pot" process configuration that does not require ionic liquid removal after pretreatment, and an engineered strain of the yeast Rhodosporidium toruloides that produces the jet-fuel precursor bisabolene as a conversion microbe. By the simultaneous processing of 48 samples, we show that this configuration and reaction conditions result in sugar yields (~70%) and bisabolene titers (~1500 mg/L) that are comparable to the efficiencies observed at larger scales but require only a fraction of the time. We expect that this Feedstocks-to-Fuels pipeline will become an effective tool to screen thousands of bioenergy crop and feedstock samples and assist process optimization efforts and the development of predictive deconstruction approaches.

Beta-blockers (β-blockers) are broadly used to manage cardiac arrhythmia, which could increase in the upcoming years due to the aging population and the increase in the number of patients with cardiac burden. In the current work, a simple, sensitive, and reliable simultaneous determination of five β-blockers (acebutolol, pindolol, atenolol, nadolol, and oxprenolol) was accomplished by ionic liquid (IL)-modified reversed-phase liquid chromatography with ultraviolet detection. The chromatographic separation was achieved on a ZORBAX® SB-C18 column using a hybrid mobile phase consisting of 50 µg/mL 1-butyl-3-methylimidazolium chloride dissolved in 0.02 mol/L phosphate buffer (pH 3.5) and acetonitrile (70 : 30, v/v). The chromatographic measurements were performed by isocratic elution at a 1.0 mL/min flow rate, 230 nm wavelength, and 25°C column temperature. The current method was applied to human plasma matrices by direct injection of samples with a short analysis time of 12 min. Good linearity was achieved in the range of 3–500 ng/L for atenolol, acebutolol, and pindolol, 7–500 ng/L for acebutolol, and 10–500 ng/L for oxprenolol with a 0.999 coefficient of determination. The limit of detection/limit of quantification values were 1.04/3.00, 2.75/7.00, 1.03/3.00, 1.05/3.00, and 3.47/10.00 ng/L for atenolol, nadolol, acebutolol, pindolol, and oxprenolol, respectively. Results of intra-day and inter-day precision were found to be less than 2%. The sensitivity enhancement factors of analytes due to the addition of IL ranged between 9- and 41-fold higher than that achieved in the absence of IL. Therefore, the proposed method could be used as a simple and sensitive analytical method for routine clinical analysis of β-blockers with the presence of a small amount of IL. [ABSTRACT FROM AUTHOR]

A new synthetic approach has emerged for constructing 9 H -pyrrolo[1,2- a ]indole scaffolds by the reactions between indoles and chalcones under metal- and solvent-free conditions at 80 °C. The reaction occurs smoothly in the presence of a Brønsted acidic ionic liquid, 1-methyl-3-(4-sulfobutyl)-1 H -imidazol-3-ium tosylate, as a catalyst, permitting the synthesis of the desired products with satisfactory yields. The developed protocol is applicable to the construction of biologically important pyrrolo[1,2- a ]indole derivatives from easily accessible chalcones having various substituents. The process commences with Michael addition to chalcones, followed by annulations induced by the elimination of a water molecule, yielding the 9 H -pyrrolo[1,2- a ]indole scaffolds. Several control experiments were carried out to achieve a better understanding of the reaction pathway. The feasibility of recycling the catalyst was also demonstrated. This method produces water as the sole byproduct and represents a green synthetic protocol. The clean reaction, easily accessible reactants, and the metal- and solvent-free and environmentally friendly reaction conditions are the notable advantages of this procedure. [ABSTRACT FROM AUTHOR]

[Display omitted] Experimental information on the molecular scale structure of ionic liquid interfaces is controversial, giving rise to two competing scenarios, namely the double layer-like and "chessboard"-like structures. This issue can be resolved by computer simulation methods, at least for the underlying molecular model. Systematically changing the anion type can elucidate the relative roles of electrostatic interactions, hydrophobic (or, strictly speaking, apolar) effects and steric restrictions on the interfacial properties. Molecular dynamics simulation is combined with intrinsic analysis methods both at the molecular and atomic levels, supplemented by Voronoi analysis of self-association. We see no evidence for the existence of a double-layer-type arrangement of the ions, or for their self-association at the surface of the liquid. Instead, our results show that cation chains associate into apolar domains that protrude into the vapour phase, while charged groups form domains that are embedded in this apolar environment at the surface. However, the apolar chains largely obscure the cation groups, to which they are bound, while the smaller and more mobile anions can more easily access the free surface, leading to a somewhat counterintuitive net excess of negative charge at the interface. Importantly, this excess charge could only be identified by applying intrinsic analysis. [ABSTRACT FROM AUTHOR]

Membrane‐based CO2 separation is a promising technology compared to traditional processes, presenting advantages such as superior energy efficiency and reduced operational costs. This study investigates the enhancement of CO₂/N₂ separation performance by incorporating ionic liquid [hmim][Tf₂N] into polysulfone membranes. The membranes were produced with 5, 10, and 20 wt% IL, and their permeability was measured at 25°C under pressures of 1 and 4 bar. Stability tests were also conducted. At 1 bar, the membrane with 20 wt% IL exhibited the highest CO₂ permeability of 342.27 Barrer, while the membrane with 5 wt% IL demonstrated the best ideal selectivity for CO₂/N₂ of 27.87. At 4 bar, the membrane with 5 wt% IL showed the highest ideal selectivity for CO₂/N₂ of 40.81, with a CO₂ permeability of 144.26 Barrer. Leaching tests indicated potential integrity loss in ionic liquid composite polymer membranes at high pressures. Specifically, the CO₂ permeability of the PSF‐[hmim][Tf₂N] 5 wt% membrane increased continuously post‐testing due to IL leaching. However, the performance of the membranes remained stable at lower pressures (1 bar). These findings suggest that the produced membranes achieve higher permeability, CO₂/N₂ selectivity, and CO₂ diffusivity, making them suitable for post‐combustion gas separation applications. [ABSTRACT FROM AUTHOR]

The performance of solid‐state lithium‐metal batteries (SSLMB) is often constrained by the low ionic conductivity, narrow electrochemical window, and insufficient mechanical strength of polyethylene oxide (PEO)‐based electrolytes. Inspired by the soft‐outside, rigid‐inside structure of starfish, we designed multifunctional “starfish‐type” composite polymer electrolytes (CPEs) using electrospinning technology. These CPEs feature a three‐dimensional rigid skeleton network composed of polyacrylonitrile/metal–organic frameworks/ionic liquids (PAN/MOFs/ILs), creating continuous and efficient Li+ transport channels: MOFs impart rigidity, PEO acts as a cushioning outer layer to enhance interfacial compatibility, and ILs reduce interfacial resistance. The resulting CPEs exhibited excellent ionic conductivity (4.37×10−4 S cm−1), a wide electrochemical window (5.34 V), uniform lithium‐ion flux, and a high transference number (0.69). Leveraging these synergistic advantages, the Li/CPEs/Li symmetric cell demonstrated outstanding dendrite suppression for over 1300 hours, and the LiFePO4/CPEs/Li cell retained 90.1 % capacity after 2100 cycles at 1.0 C, which is the best performance reported for SSLMB with MOF/PEO. The formation of multi‐component solid‐electrolyte interphase and its role in stabilizing lithium metal cycling were systematically elucidated through theoretical simulations and spectroscopic analysis. This nature‐inspired design provides a promising strategy for the development of stable solid‐state electrolytes with extended lifespans. [ABSTRACT FROM AUTHOR]

We report on the synthesis of amphiphobic fluorinated surface‐active ionic liquid (FSAIL) epoxidation catalysts, which show reversible temperature‐controlled solubility in water. The solubility of FSAILs containing the catalytically active perrhenate‐ and tungstate anions was studied in both the aqueous and the substrate phase, showing a significant solubility decrease in both media compared to their non‐fluorinated congeners. It was shown that both the epoxide product and the catalyst additive phenylphosphonic acid (PPA) are efficient in transferring the FSAIL catalyst into the organic phase, rendering the reaction homogeneous. The FSAILs were used as catalysts for the epoxidation of olefins using aqueous H2O2 as oxidant, showing an exceptionally high catalytic activity at mild conditions. Catalyst recycling was demonstrated over ten consecutive runs by phase separation and subsequent product distillation. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION To overcome the deficiency of pure starch in film‐forming performance, ionic liquids (ILs) have been introduced when preparing a homogeneous blend of starch and fiber. It is essential to select the appropriate ratio of starch to fiber and evaluate the film‐forming property of the resulted composites. In the present study, 1‐ethyl‐3‐methylimidazolium chloride ([EMIM]Cl) was used to prepare composites of soybean fiber (SF) and corn starch (CS) at various ratios. The gelatinization properties, water holding capacity, expansibility and film‐forming properties of CS‐SF composites were measured.The results showed that the composites had good water holding capacity and expansibility. They easily dissolved in water to form a low‐viscosity solution, which contributed to improve their film‐forming performance. Furthermore, the addition of SF improved the mechanical and barrier properties of the film, and composites with higher SF content exhibited excellent film pliability that remained flexibility even after 30 days of storage.The findings demonstrate that the ratio of corn starch to soybean fiber will affect the film‐forming properties of the composites formed in [EMIM]Cl. The CS‐SF composite film with a CS to SF ratio of 1:1 exhibited the best overall performance. The performance improvement of these CS‐SF composite films may be attributed to the molecular entanglement or intermolecular interaction between starch and fiber. These findings provide valuable information for the development of degradable starch‐fiber composite films. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Nickel selenide (NiSe) and carbon nanotubes (CNTs) heterojunction structure water electrolysis catalyst was prepared by vapor deposition method, constructing a heterogeneous phase interface between NiSe and CNTs. The interface effect between NiSe and CNTs enhanced further π-electron delocalization of CNTs, increasing the local electron density at the Ni sites. Subsequent ionic liquids (ILs) treatment further resolved the aggregation issues of NiSe nanoparticles and carbon nanotubes, and facilitated further π-electron delocalization at the heterojunction. The imidazolium cations acted as "connectors," tightly linking the CNTs and NiSe nanoparticles. The NiSe/CNT-IL exhibited an HER overpotential of 82 mV at 10 mA cm⁻2 in 1 M KOH. Additionally, as a full water electrolysis catalyst in a water electrolyzer, it achieved a single-cell voltage of 1.965 V at a maximum current density of 500 mA cm⁻2 at 60 °C. This direct IL functionalization for CNTs facilitates the electron transfer process and ILs can serve as the electron acceptor with superior hydrogen adsorption. • The delocalization of electrons in the carbon nanotubes is enhanced, increasing the electron density near the Ni sites. • The ionic liquid improves the dispersion of carbon nanotubes. • The ionic liquid coats the catalyst surface, stabilizing catalyst particles and enhancing catalytic activity and selectivity. • The hydrophilicity of the catalyst is improved. [ABSTRACT FROM AUTHOR]

A poly(ionic liquid) probe material was prepared that is conductive, uniformly film-forming, and rich in I2 interaction sites by structural design. Green and pollution-free electrochemical detection of gaseous I2 was achieved based on the variation of redox peak currents, and the limit of detection was 1.44 nM. The differences in redox peak potentials were utilized for the specific detection of gaseous I2. [ABSTRACT FROM AUTHOR]

Cations in ionic liquids (ILs) are typically derived from ammonium or phosphonium structures with long alkyl chains, and it is well established that the central atom significantly influences the properties of the resulting ILs. In this study, an arsonium-based IL, trihexylmethylarsonium bis(trifluoromethylsulfonyl)amide, was synthesized. The arsonium cation was found to contribute to lower viscosity and higher ionic conductivity, while maintaining sufficient stability compared to its phosphonium counterpart. [ABSTRACT FROM AUTHOR]

Metal- and solvent-free carboxylative cyclization of atmospheric CO2 with alkynol can be achieved using a 1-methylhydantoin anion-functionalized ionic liquid. 1H NMR, in situ FT-IR and DFT calculations indicate that the 1-methylhydantoin anion acts as a "pincer ligand" to form chelative interactions with the hydroxyl group, thereby effectively activating the alkynol. [ABSTRACT FROM AUTHOR]

DNA- and RNA-based diagnostics play a pivotal role in accurately detecting and characterizing health-relevant bacteria, offering insights into bacterial presence, viability and treatment efficacy. Herein, we present the development of a novel extraction protocol for both DNA and RNA, designed to enable simple and rapid molecular diagnostics. The extraction method is based on the hydrophilic ionic liquid (IL) 1-ethyl-3-methylimidazolium acetate and silica-coated magnetic beads. First, we developed an IL-based cell lysis protocol for bacteria that operates at room temperature. Subsequently, we established a magnetic bead purification procedure to efficiently and reproducibly extract DNA and RNA from the IL-lysates. The IL not only lyses the cells, but also facilitates the adsorption of nucleic acids (NAs) onto the surface of the magnetic beads, eliminating the need for a chaotropic binding buffer and allowing for purification of NAs without significant effort and materials required. Lastly, we combined the cell lysis step and the purification step and evaluated the novel IL-based extraction method on periopathogenic bacterial cultures, comparing it to commercial DNA and RNA extraction kits via (RT)-qPCR. In comparison to the reference methods, the IL-based extraction protocol yielded similar or superior results. Furthermore, costs are lower, required materials and equipment are minimal and the process is fast (30 min), simple and automatable. These characteristics favour the developed method for use in routine and high-throughput testing as well as in point-of-care, on-site and low-resource settings, thereby advancing the field of molecular diagnostics. [ABSTRACT FROM AUTHOR]

AbstractThe ionic nature of basic compounds gives rise to broad asymmetrical chromatographic peaks in RP systems containing a mixture of organic modifiers and water as mobile phases. The addition to the mobile phase of a reagent to block the silanol sites such as salts containing chaotropic anions or ILs gives significantly more symmetric peaks and a high resolution of basic analytes. In systems containing the addition of salts or ILs, the retention of ionic analytes is a consequence of the combination of a mixed mechanism that involves chaotropic, ion-exchange, hydrophobic, and ion-pairing interactions. In this work, the influence of salts consisting of various anions and ILs consisting of various cations and anions on the retention and peak symmetry of alkaloids in RP HPLC systems on C18 and Polar RP columns was investigated. The multiple interactions that salts and ILs experience inside the chromatographic system suggest that the alkaloid-suppressing potency should be measured based on the shape of the chromatographic peaks. In order to better understand the retention mechanism, the retention and symmetry of peaks obtained on both stationary phases and in systems containing salts and ILs were compared. [ABSTRACT FROM AUTHOR]

The lithium‐mediated nitrogen reduction reaction (Li‐NRR) offers a viable alternative to the Haber–Bosch process for ammonia production. However, ethanol, a common proton carrier in Li‐NRR, exhibits electrochemical instability, leading to oxidation at the anode or byproduct formation at the cathode. This study replaces alcoholic proton carriers with ionic liquids (ILs), specifically tetrabutylphosphonium chloride (TBPCl) and tetrabutylammonium chloride (TBACl), to examine how the electronegativity differences between the central atom and adjacent carbon of the cation affect catalytic performance. The results show that switching the central atom in tetraalkyl‐type ILs markedly enhances performance, specifically resulting in a 1.45‐fold increase in Faradaic efficiency (FE) with the transition from phosphonium to ammonium cation of ILs. Additionally, optimal IL concentrations in the electrolyte are identified to maximize ammonia yield. TBACl, in particular, demonstrates enhanced ammonia production and operational stability, achieving an ammonia yield rate of 13.60 nmol/cm2/s, an FE of 39.5 %, and operational stability for over 12 h under conditions of 10 mA/cm2 and 10 atm. This research underscores the potential of precise IL modifications for more efficient and sustainable Li‐NRR. [ABSTRACT FROM AUTHOR]

A bi-functional ionic liquid 1-(benzotriazole-1-methylene)-3-methylimidazole bis(2-ethylhexyl) phosphate ([BTAMIM][DEHP]) was prepared. It exhibited high activity and selectivity for the esterification of pentaerythritol with caproic acid to pentaerythritol tetra-hexanoate (PETH). Meanwhile, the friction reduction and anti-wear performance of pentaerythritol tetra-hexanoate were improved significantly by [BTAMIM][DEHP]. [ABSTRACT FROM AUTHOR]

The presence of well‐conductive polydimethylsiloxane (PDMS)‐based ionogel has changed the stereotype of PDMS of being an insulator, owing to continuous ionic liquid (IL) phase with superior ionic conductivity. However, the sacrifice on the transparency of ionogel often occurs if increasing IL content, and to overcome the immiscibility between nonpolar PDMS and polar IL is still regarded as a considerable challenge today. Herein a new strategy to prepare a transparent, highly conductive PDMS‐based ionogel with high IL content is proposed, using a "composite" surfactant of KF‐6017 and LiTFSI. Benefited from unique microphase separation during gel formation, the optimal ionogel of IG70%–1%–1% can possess excellent transparency (>95%, ~200 μm) with IL content of 70%, while owning ionic conductivity of 3.28 mS/cm and tensile property of 100 kPa. A new mechanism on the conductivity of ionogel is proposed by the molecular simulation. The ionogel can be suitable for applying as electrolyte (B) and a polymer binder for active carbon powders (as electrode A). As a result, the assembled electrochemical double‐layer capacitor (A/B/A) can be flexible accompanied with excellent electrochemical performance, which exhibits a promising future for flexible electronics and wearable devices. [ABSTRACT FROM AUTHOR]

Ultrafiltration polymer inclusion membranes (UPIMs) have become increasingly significant for the separation and purification of heavy metals from industrial wastes and wastewater due to their convenience compared to other liquid membranes. A novel process for cadmium separation and recovery has been developed using biodegradable ion carriers, specifically room temperature ionic liquids with various molecular structures. This innovation has greatly enhanced the efficiency and application of UPIMs for cadmium separation, while also providing the membranes with unique functional properties. In this study, various UPIMs were produced using polyvinyl fluoride hexafluoropropylene (PVDF‐co‐HPF) as the base polymer, different plasticizers, and symmetric room temperature ionic liquids as ion carriers. The ability of these membranes to extract cadmium ions was evaluated, demonstrating a removal rate of 9.70 μmol s−1 from a 25 ppm Cd(II) solution under optimum conditions. The selectivity and stability of the optimized UPIM were examined under different conditions to obtain a deeper insight into of its performance. The morphological characteristics of the optimized UPIM were examined using scanning electron microscopy and atomic force microscopy techniques. [ABSTRACT FROM AUTHOR]

The coating of heterogeneous catalysts with ionic liquids enables precise tuning of catalytic activity and selectivity. Recently, the fundamentals of solid catalysts with ionic liquid layers have been extensively studied. So far, investigations have focused on simple ILs without specialized functional groups. In our current work, we aim to involve functionalized ILs to take advantage of the interactions between these functional groups, the catalyst, and the reactants. In this study, we investigated the interaction, and thermal stability of the carbonyl‐functionalized IL [5‐oxo‐C6C1Im][NTf2] on Pt(111) by infrared reflection absorption spectroscopy and scanning tunneling microscopy. In addition, we performed density functional theory calculations to support our interpretation. At 200 K and low coverage, the carbonyl group of the [5‐oxo‐C6C1Im]+ cation is oriented parallel to the Pt(111) surface. With increasing coverage, the alkyl chain detaches from the surface and orients towards the vacuum. The [NTf2]− anion adsorbs parallel to the surface via the oxygen atoms of the SO2 groups. At higher coverage, at least one of the SO2 groups completely detaches from the surface. Upon heating to 250 K, we observe decomposition and partial desorption of [5‐oxo‐C6C1Im][NTf2], with further decomposition and desorption occurring between 350 and 400 K. [ABSTRACT FROM AUTHOR]

We synthesized and characterized a novel, task-specific ionic liquid for metal extraction with considerably reduced leaching behavior compared to similar, phosphonium-based ionic liquids. The synthesis involves the design of the novel compound [TOPP]2[PAM] featuring both a highly hydrophobic cation and a functional anion. The characterization of the novel ionic liquid confirmed the formation of the desired structure and sufficient purity. The high viscosity of [TOPP]2[PAM] is responsible for the comparably high working temperature of 50°C. Extraction experiments demonstrated the suitability of [TOPP]2[PAM] for extracting Sc, Th and U from aqueous matrices, whereby extraction efficacies of 87.3% ± 9.1% (Sc), 95.8% ± 2.3% (Th) and 92.7% ± 0.3% (U) were achieved over 24 h. Furthermore, Sc could be separated to a high degree via selective extraction from Th as well as from the rare earth elements Y, La, Ce, Nd, Eu, Ho and Lu. Th was separated from La, Ce, Nd, Eu, Ho and Lu at pH 1.00. During all extraction experiments, leaching into the aqueous extraction matrix peaked at only 0.134% ± 0.011% after 24 h. The loading capacities for [TOPP]2[PAM] differed between the investigated metals, the highest values being achieved for U. After extraction, 82.7% ± 2.8% of the extracted Sc could be recovered from the IL using nitric acid (10%), but less of Th and U. [ABSTRACT FROM AUTHOR]

Ionic liquids, nonvolatile salts featuring a melting point below 100 °C, are one of the few alternative solvents for environmentally friendly processes. However, like most molecular solvents, they are usually prepared by means of building blocks derived from fossil oil. Fortunately, an increasing number of ionic liquids are synthesized starting from renewable natural products such as sugars and amino acids. In the present review, we describe the detailed synthesis and applications of the biosourced ionic liquids reported in the literature over the last four years. 1 Introduction 2 Carbohydrate-Based Ionic Liquids 3 Amino Acid Based Ionic Liquids 4 Terpene-Based Ionic Liquids 5 Miscellaneous Ionic Liquids 6 Conclusion [ABSTRACT FROM AUTHOR]

Ionic liquids have been utilized in numerous significant applications within the field of chemistry, particularly in organic chemistry, due to their unique physical and chemical properties. In the realm of asymmetric transition-metal-catalyzed transformations, chiral ionic-liquid-supported ligands and their corresponding transition-metal complexes have facilitated these processes in unconventional solvents, especially ionic liquids and water. These innovative reaction systems enable the recycling of transition-metal catalysts while producing optically active organic molecules with comparable or even higher levels of chemo-, regio-, and stereoselectivity compared to their parent catalysts. In this short review, we aim to provide an overview of the structures of chiral ionic-liquid-supported ligands and the synthetic pathways for these ligands and catalysts. Various synthetic methodologies are demonstrated based on the conceptual frameworks of diverse chiral ionic-liquid-supported ligands. We systematically present the structures and comprehensive synthetic pathways of the chiral ionic-liquid-supported ligands and the typical corresponding transition-metal complexes that have been readily applied to asymmetric processes, categorized by their parent ligand framework. Notably, the crucial experimental procedures are delineated in exhaustive detail, with the objective of enhancing comprehension of the pivotal aspects involved in constructing chiral ionic-liquid-tagged ligands and compounds for both scholars and readers. Considering the current limitations of such ligands and catalysts, we conclude with remarks on several potential research directions for future breakthroughs in the synthesis and application of these intriguing ligands. [ABSTRACT FROM AUTHOR]

N,N′-Dialkylimidazolium-based ionic liquids are capable of completely dissolving lignocellulosic biomass at elevated temperatures and are considered as promising green solvents for future biorefining technologies. However, the obtained ionic liquid lignin preparations may contain up to several percent nitrogen. This indicates strong interactions between the biopolymer and the IL cation, the nature of which has not yet been clarified. The present study investigates mechanisms and pathways of the formation of nitrogen-containing lignin compounds. To achieve this goal, eight monomeric lignin-related phenols bearing different functional groups (ketone, aldehyde, hydroxyl, carbon–carbon double bonds) were treated with 1-butyl-3-methylimidazolium acetate (BmimOAc) under typical conditions of IL-assisted lignocellulose fractionation (80–150 °C). A number of the resulting products were tentatively identified, for all the studied model compounds, by two-dimensional NMR spectroscopy and high-performance liquid chromatography—high-resolution mass spectrometry. They all possess covalently bonded Bmim residues and occur through the nucleophilic addition of an N-heterocyclic carbene (deprotonated Bmim cation) to electron-deficient groups. The reactivity of lignin functional groups in their interaction with Bmim is greatly affected by the temperature and dissolved oxygen. IL's thermal degradation products act as additional reactive species toward lignin, further complicating the range of products formed. The obtained results made it possible to answer the question posed in this article's title and to assert that N,N′-dialkylimidazolium-based ILs act as active reagents with respect to lignin during the dissolution of lignocellulose. [ABSTRACT FROM AUTHOR]

Pure organic films consisting of polypyrrole, polyaniline and a composite of polypyrrole and polyaniline electrodeposited in the ionic liquid EMIM‐TFSI onto mesoporous carbon electrodes are tested for their hydrogen evolution reaction capabilities. The use of these intrinsically conducting polymers is seen as a way of stepping away from expensive and rare metallic catalysts. Co‐polymerisation of polypyrrole and polyaniline in a 1 : 10 ratio in EMIM‐TFSI was found to be doped with the TFSI− anion and be much more active to the hydrogen evolution reaction when compared to pure polymers. Tafel analysis of the composite gave a value of 144 mV/dec indicating that the Volmer step is the rate limiting step. However, stability tests showed an improvement in the composite's overpoential performance for the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]