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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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

Smart aqueous two-phase systems (ATPSs) were fabricated using ferrocenyl and benzyl-modified poly(ionic liquid)s for the first time. The novel ATPSs were found to be pH-sensitive. The upper phase and lower phase could be inverted reversibly by adjusting the pH value of the ATPSs. [ABSTRACT FROM AUTHOR]

In this work, we report a rare ionic covalent organic framework (named as ECUT-iCOF-5) synthesized by the Knoevenagel reaction using an ionic liquid monomer. ECUT-iCOF-5 is found to show a promising potential for gold extraction with a high extraction ability towards gold, including a high extraction capacity (3260 mg g−1), good selectivity over both cations and anions, and good recycle use (at least six times). [ABSTRACT FROM AUTHOR]

In this paper, the ionic liquids Met-1, Met-2, Asp-1 and Asp-2 were prepared by acid-base neutralization reactions with different molar ratios of amino acids (methionine and aspartic acid) and concentrated sulfuric acid as raw materials. Four ionic liquids were formulated into different concentrations of inhibitors, and their hydration inhibition and inhibition mechanism were investigated by anti-expansion experiment, linear swelling experiment and flocculation experiment. The results showed that when the molar ratio of aspartic acid to concentrated sulfuric acid was 1:1.5, which was named Asp-2, and the concentration of Asp-2 was 1.0%, the inhibitor achieved the best hydration inhibition performance on clay with 91.95% anti-swelling rate and 21.37% linear swelling rate. Infrared spectra (FT-IR) analysis, thermogravimetric analysis (TGA), and laser particle size analysis were used to investigate the inhibition mechanism of Asp-2. The results showed that the average particle size of the hydrated soil samples increased by 0.282 μm and the median particle size increased by 2.101 μm after the addition of Asp-2 inhibitor, indicating that Asp-2 inhibitor played a good inhibitory role in the drilling fluid. [ABSTRACT FROM AUTHOR]

Green chemicals and their applications to textiles became popular for imparting specific functional properties. Because of their complicated applications, the production of multifunctional textiles consumes high energy and produces high amount of wastewater. Therefore, in this study, an innovative one-step approach was used in order to obtain multifunctional cotton fabrics. Montmorillonite/Ionic Liquid (MMT-IL) nanocomposites were formed by using 3 different ionic liquids [IL1 (1-Methyl-3-butylimidazolium chloride, IL2 (1-Methyl-3- octylimidazolium tetrafluoroborate), and IL3 (1-Methyl-3-octylimidazolium bromide)], at 3 different concentrations determined which were based on the cation exchange capacity (CEC) of the montmorillonite clay mineral and MMT-IL nanocomposites. The synthesized MMT-IL nanocomposites were applied to the cotton fabrics by pad-dry-cure method. The pad-dry-cure process was carried out on fabrics also by using 2 different crosslinkers. Modified ethylene urea (MDEU) and (3-Chloropropyl)trimethoxylane (CPTES) were used as crosslinkers. Structural, thermal and surface properties of the MMT-IL nanocomposites and the treated fabrics were determined by FTIR, XRD, TGA, and SEM–EDS analyses. The performance properties of untreated and MMT-IL nanocomposite-modified fabrics were investigated. In order to determine multifunctional properties, antimicrobial, flame retardancy and conductivity values were examined according to the standards. In addition, whiteness index values were also measured to determine whether the MMT-IL nanocomposite modification affected the appearance properties of the fabrics. The performance properties of the fabrics were detailed by using the Box-Behnken experimental design. This paper describes the synthesis and application of Ionic Liquid-Clay Nanocomposites to cotton fabrics. The IL-MMT treated fabrics gained antimicrobial, flame retardant, and conductive properties. [ABSTRACT FROM AUTHOR]

New supercritical carbon dioxide ( s c C O 2 )-based cutting fluids combining the cooling from s c C O 2 and lubrication from various additives are investigated in this study. Selected components, including ionic liquids, vegetable and mineral oils, water, and PEG, were introduced into supercritical C O 2 , and tribological tests were performed on a CNC lathe to analyze their influence on Ti6Al4V/WC-Co contact. Forces and temperatures were recorded to compare the perfomances of the sc C O 2 -lubricant mixtures for future use in machining. The analysis of the apparent friction coefficient and sticking zone showed a noticeable decrease by ionic liquids when combined with sc C O 2 at a speed of 100 m/min and 4 mL/min delivery flow rate. The other lubricants (water and PEG vegetable oils) performed similarly to standard mineral oil and are less expensive, which could help in developing future low-cost yet effective cooling and lubrication methods for the machining industry. [ABSTRACT FROM AUTHOR]

To explore the influence of reaction medium on the copolymerization behavior of acrylamide‐based copolymers, three types of copolymers (P(AM‐St)(ILs), P(AM‐MMA)(ILs), and P(AM‐AMPS)(ILs)) were synthesized by combining insoluble, slightly soluble, and easily soluble monomers with acrylamide in the 1‐butyl‐3‐methylimidazolium tetrafluoroborate ([BMIM]BF4) reaction medium. The reactivity ratio, Fourier transform infrared spectroscopy, 1H NMR spectroscopy, elemental analysis, and scanning electron microscopy were employed to characterize the copolymers' properties. The results indicated that in [BMIM]BF4 copolymerization, the reactivity ratio of AM and St in P(AM‐St)(ILs) decreased, the reactivity ratio of AM in P(AM‐MMA)(ILs) will increase. While the reactivity ratio of MMA will decrease. The reactivity ratio of AM in P(AM‐AMPS)(ILs) will increase and the reactivity ratio of AMPS will decrease. The distribution of AM and St segments in P(AM‐St)(ILs) molecular chains is more uniform and compact. When AM polymerizes with hydrophobic monomers (St) in [BMIM]BF4, its copolymer solution exhibits lower viscosity loss rates in temperature, shear, and salt resistance tests. Therefore, ionic liquids are more suitable as reaction media for the synthesis of hydrophobic‐modified polyacrylamides, which facilitate a more uniform distribution of hydrophobic monomers within the copolymer chains and exhibit enhanced resistance to temperature, salt, and shear stresses. [ABSTRACT FROM AUTHOR]

The utilization and transformation of CO2 under mild conditions, particularly at ambient pressure and moderate temperature, remain challenging and attract widespread attention. Ionic liquids are considered to be green and designable solvents, and have high efficiency for CO2 conversion. Here, a novel aprotic ionic liquid, [Ch][Triz], was discovered as a dual-functional catalyst capable of simultaneously activating CO2 and the substrates, and exhibited outstanding performance in catalyzing the cyclization of CO2 and 2-aminobenzonitriles under solvent-free and mild conditions (such as 0.1 MPa, 30–50 °C), affording a range of quinazoline-2,4(1H,3H)-diones in high yields. Furthermore, [Ch][Triz] IL could be easily recovered and reused up to five recycle runs without obvious activity loss. This work proposes a sustainable approach to CO2 conversion, and holds great potential for quinazoline-2,4(1H,3H)-dione preparation under mild conditions. [ABSTRACT FROM AUTHOR]

A facile and highly efficient protocol has been developed for the synthesis of extensively functionalized, fully substituted N‐methyl‐1,4‐dihydropyridines. This approach is a one‐pot pseudo‐three‐constituent cyclo‐condensation of aromatic aldehydes with (E)‐N‐methyl‐1‐(methylthio)‐2‐nitroethenamine (NMSM). This reaction presumably entails the Knoevenagel reaction followed by Michael addition and regioselective N‐cyclization with removing methanethiol and producing two C─C bonds and one C─N bond. The key advantages of this strategy include an optimized reaction time, achieving moderate to excellent yields, a straightforward experimental procedure, and the use of the ionic liquid 1‐ethyl‐3‐methylimidazolium acetate [(EMIM)Ac] as the catalyst. The resulting derivatives were well characterized by IR, 1H NMR, 13C NMR, and HRMS. [ABSTRACT FROM AUTHOR]

Diverse libraries of biaryls/heterobiaryls were synthesized by aryl/hetero‐aryl tosylates as coupling partners in the ligand‐free, Ni‐catalyzed Suzuki coupling reaction, and Pd‐catalyzed Hiyama cross‐coupling reaction in ionic liquids (ILs) as green solvent. In this method easily available and economically viable tosylates were coupled with readily available boronic acids and phenyltriethoxysilanes in Suzuki and Hiyama cross‐coupling respectively to yield the corresponding biaryls/heterobiaryls. Mild reaction condition(s), easy workup, moderate to excellent yield of the isolated pure products, wide substrate scope, and recycling/reuse of the ILs are the advantages of this method over the other reported methods. [ABSTRACT FROM AUTHOR]

The energy storage capability of supercapacitors (SCs) strongly depend on the operating cell voltage of the electrolytes of choice. In this regard, the inherent distinct electrochemical stability of cations and anions is a factor of relevance for the operating cell voltage. The use of double salts sharing one ion has been described as an approach to circumvent this problem, but whether modifying the solvation structure of cations and anions with different solvent molecules (coordinating and/or non‐coordinating) could help balance their electrochemical stability in SCs has not yet been fully addressed. In this work, electrolytes are prepared by combining solvent mixtures and double salts, specifically 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIMTFSI) and 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMIMBF4) in mixtures of water (H2O) and dimethysulfoxide (DMSO) as coordinating co‐solvents and acetonitrile (CH3CN) as a weakly coordinating one. It is found that the presence of this latter one helped to enhanced the cation solvation structure (above 9). This increase of the entropic features allows operating at cell voltages of up to 2.2 V and the subsequent enhancement of the energy storage capabilities and capacitance retentions (up to 15 Wh kg−1 and ≈87% after 10 000 cycles, respectively). [ABSTRACT FROM AUTHOR]

Mixed matrix membranes (MMMs) with enhanced selectivity and permeability are investigated by incorporating deep eutectic solvents (DES) functionalized CeO2 as fillers. DES is well known owing to the intrinsic benefits of low cost, environmentally friendly, biodegradable, and CO2 philic nature. Characterization confirms the collaboration of polymer and functional CeO2 fillers. Experiments of gas separation show that the introduction of DES‐modified CeO2 fillers (2%–15%) significantly improves CO2 penetrability from 27 to 48 Barrer. The ideal separation factor of CO2/CH4 and CO2/N2 also increases from 46 to 62 and 60 to 86, respectively, with increasing filler percentage. MMMs correspond to the superior gas separation performance compared with DES liquid membranes. The collaboration between DES‐treated CeO2 and CO2 contributes to the improved results. The fabricated MMM films are tested under operating parameters, confirming the potential of ceria modified fillers for CO2 capture applications. This research reveals the advancements achieved by incorporating DES‐functionalized CeO2 fillers in MMMs, enhancing selectivity and permeability for CO2 capture. These findings correspond to the development of effective and viable membrane technologies for various industrial applications. [ABSTRACT FROM AUTHOR]

In cold methanol, energetic ionic liquid 1-n-propyl-3-vinyl-imidazol-1-ium perchlorate, 1, crystallizes in the presence of excess Ba(ClO4)2, 2, into tetrakis 1-propyl-3-vinyl-imidazol-1-ium·barium hexa-perchlorate, 3. Crystals of 3, with molecular formula (C8H13N2)4·BaCl6O24, are colorless and monoclinic, with space group P21/c. The crystal structure is characterized by a dodecahedral coordination around the barium atom, with each perchlorate chelating Ba2+ in a κ2O,O' fashion, and the Ba(ClO4)64− anion is surrounded by four imidazolium cations. [ABSTRACT FROM AUTHOR]

The ILs ([Li (synthetic esters)] NTF2) were prepared by the in situ synthesis method. The tribological behaviour of the ILs to friction pairs of Ti‐6Al‐4V titanium alloy against silicon nitride was studied by SRV‐V under different concentrations and friction frequencies; the wear scar was studied by SEM, XPS and TOF‐SIMS. The results showed that the friction coefficient and wear loss decreased gradually with the increase of the LiNTF2 content; when the LiNTF2 content reached a certain value (10%), the friction coefficient and wear loss did not change much. Tribofilm composed of titanium oxide, Al2O3, TiFO2, AlOF2, Ti2O4F and Al2O3F plays a major role in lubrication and anti‐friction effect. [ABSTRACT FROM AUTHOR]

The primary objective of this study was to investigate the ability of seven ionic liquids (ILs), NaBF4 salt, and five deep eutectic solvents (DESs) to extract five cannabinoids from hemp tea. Among the solvents examined, 1-butyl-3-methyl-imidazolium chloride (BMIMCl) proved to be a promising solvent for the recovery of cannabinoids, and it was selected for the subsequent optimization of ultrasound-assisted extraction (UAE) using response surface methodology (RSM). The optimized theoretical conditions were as follows: 0.071 M BMIMCl, a solvent-to-solid ratio of 24.15 mL/g of dried hemp tea material, and an extraction time of 20.80 min. These conditions resulted in theoretical extraction yields of 98.34 μg/g for sample material for cannabichromene (CBC), 1104.69 μg/g for cannabidiol (CBD), 209.64 μg/g for Δ9-tetrahydrocannabinol (Δ9-THC), 40.43 μg/g for cannabinol (CBN), and 55.49 μg/g for cannabigerol (CBG). For comparison purposes, the optimized extraction parameters were applied to three more cannabis teas, originating from the Netherlands, Greece, and Italy. The analysis revealed varying levels of detected cannabinoids and exhibited levels of Δ9-THC, ranging from 34.93 ± 0.24 μg/g to 199.46 ± 1.02 μg/g. Consequently, these findings have significant regulatory implications, as none of the examined hemp tea samples met the permitted zero tolerance threshold for Δ9-THC. [ABSTRACT FROM AUTHOR]

We studied the liquid structures and dynamics of a series of dual-functionalised ionic liquids (DFILs) by Md simulations. The studied DFILs consist of functionalised imidazolium cations with a nitrile group and varying lengths of ether side chains, paired with bis(trifluoromethyl sulfonyl) imide anions, denoted as [C2CNIm(EtO)nMe][Tf2N]. We instigated distribution functions, Voronoi tessellation, and cluster analysis, to probe the liquid structures. Furthermore, we explored dynamic properties such as mean-square displacements (MSD), self-diffusivity coefficients, hydrogen bonding, ion pairing, and ion cage effects. Our findings revealed a correlation between the length of the ether side chains and the density of the studied DFILs when the longer side chains lead to a decreased density. Calculated partial radial distribution functions (PRDF) of ether side chains of the cations demonstrated a tendency for self-aggregation as the chain length increased. The combined distribution functions diagrams show that the hydrogen bond between ions is more pronounced for cations with smaller side chains. Anions displayed higher diffusivity than the cations, and among the cations, [C2CNIm(EtO)6Me]+ has the lowest diffusion coefficient. Various methods evaluated the micro-heterogeneity dynamics of DFILs. [ABSTRACT FROM AUTHOR]

Climate change is considered one of the main challenges in this century, and CO2 emissions significantly cause it. Integrating CO2 capture, storage, and conversion is proposed to solve this problem. 1-Butyl-3-methylimidazolium chloride ([Bmim]Cl) ionic liquid was employed to capture and store CO2 from the air and subsequently converted into CO using non-thermal plasma. Moreover, we also tested the CO2 capture and storage capacity of water from different sources, e.g., Milli-Q, deionized water, and tap water. [Bmim]Cl solution captured CO2 from the air and then converted to CO after 24 h using plasma. In comparison with water (Milli-Q water, deionized water, and tap water), CO production was increased by 28.31% in the presence of water (Milli-Q water, deionized water, and tap water) + [Bmim]Cl. It suggests that this method could be a promising way to capture, store, and convert CO2 from air at atmospheric pressure and room temperature as an effort to reduce carbon emission. [ABSTRACT FROM AUTHOR]

Water stability is one of the most important factors restricting the practical application of metal organic frameworks (MOFs). In this work, we fabricate a highly defective HKUST-1 framework with a mixed valence of CuI/CuII by mechanical ball milling method. This defective HKUST-1 is embellished by functionalized ionic liquids as hydrophobic armor, making the hybrid HIL1@HKUST-1 exhibits outstanding water stability, remarkable SO2 adsorption (up to 5.71 mmol g-1), and record-breaking selectivity (1070 for SO2/CO2 and 31,515 for SO2/N2) at 25 °C and 0.1 bar, even in wet conditions. [ABSTRACT FROM AUTHOR]

Shale hydration and expansion during drilling can lead to wellbore instability, sticking, and frequent leakage accidents. To prevent these issues, an ionic liquid (IL) inhibitor solution was synthesized using DL‐alanine and 98% concentrated sulphuric acid as raw materials. The optimum composition and effect of the synthesized inhibitor in oilfield water‐based drilling fluids were evaluated through anti‐expansion, linear expansion rate, water washing resistance, and clay hydration dispersion experiments. The inhibition mechanism was investigated by thermogravimetric analysis, infrared spectroscopy, zeta potential, contact angle, and X‐ray diffraction analysis. The results show that the optimum IL consists of a 1:1 molar ratio of DL‐alanine to concentrated sulphuric acid synthesized under a reaction temperature and time of 70°C and 18 h, respectively. The resulting DL‐alanine IL exhibited the best inhibitory effect on the hydration, dispersion, and expansion of clay at a concentration of 0.5% in aqueous solution, and its linear expansion rate was only 18.49%. After adding a quantitative amount of clay to different concentrations of DL‐alanine IL aqueous solution, the expansion volume of the clay decreased and the water washing resistance significantly improved. These results provide a theoretical basis for improving the safety and efficiency of shale horizontal well drilling operations. [ABSTRACT FROM AUTHOR]

We have unveiled a highly effective environmentally friendly protocol utilizing a single-vessel, multi-component approach for the production of benzo[4,5]imidazo [1,2-a]pyrimidine-3-carbonitrile and tetrahydrobenzimidazo [2,1-b]quinazolin-1(2H)-one derivatives using [C4(DABCO)2].(CuCl4) as a novel and powerful catalyst. The newly prepared catalyst was fully characterized by Fourier-transform infrared (FT-IR), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), and field emission scanning electron microscopy (FESEM) analysis. The key advantages of this novel procedure include short reaction times, enhanced product yields, a straightforward purification process and a benign impact on the environment because of the solvent-free nature of the reaction conditions and reusability of the promoter. [ABSTRACT FROM AUTHOR]

The accurate monitoring of lactate level is very important in the fields of food quality and sport. In the present work, an effective sensor was introduced for lactate monitoring in food and in human bio-fluid. The non-enzymatic electrochemical sensor was fabricated by bulk modification of a simple carbon paste electrode (CPE) with iron-copper ferricyanide (ICF) catalyst and room temperature ionic liquid (IL). The lactate sensing capabilities of the suggested sensor are significantly enhanced due to the combination of the high conductivity of IL and the improved catalytic properties of the ICF modifier. The chronoamperometric response measurements of the ICF-IL-CPE demonstrated a high sensitivity towards lactate across a broad linear range of 20 to 1000 µM, with a correlation coefficient of R2 = 0.999. This sensor also exhibited a detection limit of 4.5 µM, a reproducibility of 3.9% relative standard deviation, and a stability of 95.8% over a period of five weeks. The suggested ICF-IL-CPE depicted minimal background interference against common interfering species. This makes it a highly promising tool for accurately measuring lactate concentrations in various samples including saliva from athletes and cow milk. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are promising solvents for separating aromatics from fuel oils. However, studies for separate polycyclic aromatics with ILs are rare and insufficient, and the impact of solute structure on extraction performance still needs to be determined. In this work, we use 1‐ethyl‐3‐methylimidazolium bis([trifluoromethyl]sulfonyl)imide ([EMIM][NTF2]) as an extractant to separate 1‐methylnaphthalene, quinoline, and benzothiophene from dodecane mixtures. Liquid–liquid equilibrium experiments identified the optimal operating conditions. Nine solute molecules, including five alkanes and four aromatic hydrocarbons, were used to study the relationship between extraction performance and solute structure. Molecular dynamics simulation and quantum chemistry calculations gave a deep insight and reasonable interpretation of the structure‐performance relationship at the molecular level. An industrial‐scale extraction process was proposed. The IL can be easily regenerated using heptane as a back‐extractive solvent. A high‐purity fuel oil with aromatic content below 0.5 wt% is obtained after 8‐stage extraction. [ABSTRACT FROM AUTHOR]

Ionic liquids' (ILs) surface tension, vital in liquid interface research, faces challenges in measurement methods—time‐consuming and labor‐intensive. The Structure‐Surface Tension Relationship (SSTR) is crucial for understanding the surface tension laws of ionic liquids, helping to predict surface tension and design ionic liquids that meet target requirements. In this study, SMILES string and group contribution methods were used to generate descriptors, and the random forest and multi‐layer perceptron (MLP) models were cross combined with the two descriptor generation methods to establish the SSTR model, providing a comprehensive framework for predicting the surface tension of ionic liquids. String‐MLP excels with high accuracy (R2 = 0.995, RMSE = 0.686, AARD% = 0.71%) for diverse ILs' surface tension values. Meanwhile, the Shapley Additive exPlanning (SHAP) method was used to test the impact of different features on model prediction, increasing the transparency and interpretability of the model. [ABSTRACT FROM AUTHOR]

A characteristic feature of cellulose is crystal polymorphism. Among the cellulose allomorphs, cellulose IVII has been the most time-consuming and energy-intensive one to prepare from native cellulose with a cellulose I structure. In this work, we report a facile preparation method of cellulose IVII by regeneration from an ionic liquid (IL) solution. Although regeneration from arbitrary IL solutions is known to produce only cellulose II and amorphous cellulose, we found that appropriate selections of regeneration temperature (373 K), IL structure (dimethylphosphate anion paired with imidazolium cation), and cellulose concentration (5 mol%) induced the formation of cellulose IVII. With the optimal conditions, cellulose IV with crystallinity of 31% was obtained without contamination of other cellulose allomorphs. Wide angle X-ray scattering and 13C solid-state NMR measurements on cellulose/IL mixtures demonstrated that the cations and anions were rather ordered and the gt conformer of cellulose was preferred at a high temperature, which would be relevant for the formation of cellulose IVII. [ABSTRACT FROM AUTHOR]

Owing to the adverse influences of irreversible oxidation, the development of MXene‐based materials, especially those with satisfactory performance and longevity for aqueous energy storage, continues to suffer severe challenges. Herein, the strategy of targeted passivation‐supported defect‐lock‐oxygen is conceived, whereby engineered the V2CTx material for controllable partial oxidation with enhanced regioselectivity. When the material works, inside the intrinsic defects, the outward diffusion of oxidation is confined by the Lewis bases around the defects, which allows for the controllable progress of oxidation. The defect‐locked oxygen oxidizes the exposed carbon, thus forming sufficient amorphous carbons for enhancing the capacitive‐type adsorption of K‐ions. Then the oxidized defects enabled the fast kinetics via the cross‐layer transport of K‐ions. Benefiting from the strategy, the electrode assembly V2CTx‐RTIL (V2CTx equipped with room temperature ionic liquid) exhibits high capacity, good rate capability, and ultra‐longevity compared with those of the MXene materials so far reported. This work presents the first strategy of targeted passivation‐supported defect‐lock‐oxygen for high‐rate capability and super long‐cycling aqueous K+ storage and hopefully would provide the inspiration for the future design of novel electrodes. [ABSTRACT FROM AUTHOR]

Novel hydrogen-bonding-catalyzed upcycling of polyethylene glycol (PEG) waste to 1,4-dioxane over OH-functionalized ionic liquids (ILs) under mild (≥80 °C), solvent- and metal-free conditions was developed through a theoretical computation-assisted design. Notably, 1,4-dioxane was spontaneously separated due to its immiscibility with ILs. [ABSTRACT FROM AUTHOR]

Levulinic acid is an important chemical intermediate, which has many applications in organic synthesis, industry, agriculture, and medicine. In this word, three kinds of heteropoly acid based ionic liquids ([IMPS]H2PW12O40、[PyPS] H2PW12O40 [TEAPS] H2PW12O40) were used to catalyze the one‐pot conversion of cellulose to levulinic acid. [IMPS]H2PW12O40 has the highest catalytic activity due to its strong Hammett acidity (H0). In addition, the effect of biphasic solvent systems on the conversion of cellulose to levulinic acid was also studied. The results showed that the GVL/H2O system could effectively promote the conversion of cellulose and increase the yield of levulinic acid. The yield of levulinic acid could reach 52.6% and the conversion rate of cellulose was 91.2% at 180 °C for 180 min under the GVL/H2O volume ratio of 1:1 with [IMPS]H2PW12O40 as a catalyst at 1 Mpa N2 and cellulose as raw material. And [IMPS]H2PW12O40 can be recycled up to five times without significant performance loss. This study provides a promising method for efficiently converting cellulose and other biomass resources to levulinic acid extraction. [ABSTRACT FROM AUTHOR]

In this paper, we report the unusual aggregation behavior of an important cyanine dye 1,1′-diethyl-4,4′-carbocynine iodide (DECI), also known as kryptocyanine, which interestingly depends on the type of the ionic liquid (IL) present in the aqueous solutions of the dye. Notably, the presence of a small amount of ILs containing [BF4]−, [PF6]− and [OTf]− anions induced the process of J-aggregation instantly, and the added ILs acted as promoters for J-aggregation, followed by time-dependent precipitation. In contrast to the above-mentioned ILs, the presence of a small amount of ILs containing Tf2N− anions induced the process of J- and H-aggregation simultaneously, followed by time-dependent conversion of H-aggregates to J-aggregates. Furthermore, the aggregation behavior of the dye was also found to be dependent on the concentration of the dye, temperature conditions, and nature of solubilizing media (polarity of the solvent and pH). [ABSTRACT FROM AUTHOR]

One-pot ethanol production, which involves successive biomass pretreatments, enzymatic hydrolysis, and fermentation in a single vessel, is essential for practical bioethanol production. To achieve this, low-toxicity pretreatment solvents such as a zwitterionic liquid, OE2imC3C, are necessary. Although the cellulose-dissolving ability of OE2imC3C has been studied, its biomass pretreatment ability has not been thoroughly investigated. Herein, we investigated the biomass pretreatment ability of OE2imC3C at various temperatures and concentrations. The mildest conditions for successful pretreatment were 75 wt% OE2imC3C at 90 °C. On the other hand, OE2imC3C exhibited a lower pretreatment ability than [C2mim]OAc, which is the best-known cellulose-dissolving ionic liquid. The main reason for the low pretreatment ability of OE2imC3C was its high viscosity. Reducing their viscosity is a key factor for designing zwitterionic liquids with high pretreatment ability. [ABSTRACT FROM AUTHOR]