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Porous organic polymers (POPs) are a type of porous material composed of organic structural units connected by covalent bonds and POPs have been used as efficient electrocatalysts for hydrogen evolution reaction (HER). Herein, glassy carbon electrode (GCE) is chemically modified by B‐doped imidazolium‐based porous organic polymers loaded with Ru nanoparticles on the GCE surface. The incorporation of B in the POPs regulates the electronic structure of electrocatalysts to enhance their inherent electrocatalytic activity for HER. The optimized modified electrode GCE‐Ru/PIM‐Br2 exhibits a low overpotential of 271 mV at a current density of 10 mA cm−2 with a small Tafel slope (80 mV dec−1) in acidic solutions, and shows long‐term stability for up to 22 h. This work presents a strategy to develop B‐doped porous electrodes with loaded metal nanoparticles to strengthen the catalytic performance of electrocatalysts. [ABSTRACT FROM AUTHOR]

Preparing fluorocarbon surfactant for aqueous film-forming foam is a complex process. Overcoming steric hindrance when introducing imidazolium to the fluorocarbon chain is a key challenge. In this significant work, we proposed a simple one-step route to prepare imidazolium-contained fluorocarbon surfactant under mild conditions. The FT-IR, 1H NMR, 13C NMR, MS, and TG technologies characterized the imidazolium-contained fluorocarbon surfactant by analyzing functional groups, molecular weight, and thermal stability. An equimolar mixture of imidazolium-contained fluorocarbon surfactant and C6H13NaO3S demonstrated high surface activity, enabling the foam to spread effectively on commercial fuels. The spreading coefficient of foam on n-cyclohexane met the US Military Specification. Coordinatively, the foam drained in time to maintain the stability and completeness of the aqueous layer, with a moderate 25% drainage time of 317 s and a proper foam expansion ratio of 10.5. In extinguishing experiments, the imidazolium-contained fluorocarbon surfactant/C6H13NaO3 mixture extinguished test fires in 65 s, suggesting an essential potential in the aqueous film-forming foam formula. [ABSTRACT FROM AUTHOR]

Ionic liquids (IL) have emerged as the potential class of solvents for various chemical processes and reactions, including gelatinization and chemical modification of starch. Through various studies it has been established that expensive nature of ILs can be counter balanced by employing the mixture of IL/water instead of pure ILs. The IL/water system has the advantage to plasticize starch more effectively due to their synchronal effect and rational viscosity. The properties of ILs can be tempered by preferring particular cations/anions according to the specific type of starch which may be helpful in convenient dissolution and modification of starch. Starch can be modified by esterification or etherification reaction in IL medium to alter their properties and to use it in various application areas. Starch dissolution is subjected to various parameters like type of starch, nature of IL, ratio of IL/water, and temperature which has been discussed elaborately in the present review paper. [ABSTRACT FROM AUTHOR]

Several tetrahydroxidohexaoxidopentaborate(1-) salts of N-substituted diimidazolium cations or N-substituted dipyrrolidinium cations linked through N-C6-N chains have been synthesized and characterized spectroscopically (NMR, IR) and by single-crystal XRD studies: [R(NC3H3N)(CH2)6(NC3H3N)R][B5O6(OH)4]2·xH2O (R = Me, x = 0 (1); R = Et, x = 3 (2); [Me(NC3H3N)(CH2(C6H4)CH2)(NC3H3N)Me][B5O6(OH)4]2 (3), [(C4H8N)(R)(CH2)6(R)(NC4H8)][B5O6(OH)4]2·xB(OH)3 (R = Me, x = 0 (4, two polymorphs); R = Et, x = 0 (5); R = Bu, x = 4 (6); R = allyl, x = 0 (7)). Representative samples (1 and 7) were also characterized by thermal (TGA/DSC) studies; compounds are thermally decomposed to B2O3 in air. Numerous anion-anion H-bonding interactions are present in the solid-state structures of 1–5 and 7 as giant anionic networks. Unusually, in 6 there are no R22(8) anion-anion interactions as the co-crystallized B(OH)3 bridges between all pentaborate anions. H-bonding interactions in 1–7 have been examined using Etter graph set analysis; C(8), C33(18), R22(8), R22(12) and R44(12) motifs have been identified. [ABSTRACT FROM AUTHOR]

Owing to its high production volume and wide range of applications, polyethylene has gained a great deal of attention, but its low surface energy and non-polar nature have limited its application in some important fields. In this study, ethylene/11-iodo-1-undecene copolymers were prepared and used as the intermediates to afford a series of imidazolium-based ionomers bearing methanesulfonate (CH3SO3−), trifluoromethanesulfonate (CF3SO3−), or bis(trifluoromethane)sulfonimide (Tf2N−) counteranions. The tensile test results showed that the stress-at-break (7.8–25.6 MPa) and the elongation-at-break (445%–847%) of the ionomers could be adjusted by changing the counterion species and the ionic group contents. Most importantly, the ionomers exhibited marvelous antibacterial activities against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The ionomers bearing Tf2N− exhibited antibacterial activities >99% against both S. aureus and E. coli when ionic content reached 9.1%. The imidazolium-based ionomers prepared in this work demonstrated excellent comprehensive properties, especially high-efficient and broad-spectrum antibacterial ability, exhibiting the potential for the application as the antibacterial materials in packaging, medical, and other fields. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) are interesting chemical compounds that have a wide range of industrial and scientific applications. They have extraordinary properties, such as the tunability of many of their physical properties and, accordingly, their activities; and the ease of synthesis methods. Hence, they became important building blocks in catalysis, extraction, electrochemistry, analytics, biotechnology, etc. This study determined antifungal activities of various imidazolium-based ionic liquids against yeast Saccharomyces cerevisiae via minimum inhibitory concentration (MIC) estimation method. Increasing the length of the alkyl group attached to the imidazolium cation, enhanced the antifungal activity of the ILs, as well as their ability of the disruption of the cell membrane integrity. FTIR studies performed on the S. cerevisiae cells treated with the ILs revealed alterations in the biochemical composition of these cells. Interestingly, the alterations in fatty acid content occurred in parallel with the increase in the activity of the molecules upon the increase in the length of the attached alkyl group. This trend was confirmed by statistical analysis and machine learning methodology. The classification of antifungal activities based on FTIR spectra of S. cerevisiae cells yielded a prediction accuracy of 83%, indicating the pharmacy and medicine industries could benefit from machine learning methodology. Furthermore, synthesized ionic compounds exhibit significant potential for pharmaceutical and medical applications. [ABSTRACT FROM AUTHOR]

[Display omitted] The outer bacterial membrane of drug-resistant bacteria is a significant barrier to many antimicrobials. Therefore, the development of new antibacterials primarily focuses on damaging the outer bacterial membrane of Gram-negative bacteria. Among many membrane-disrupting substances, the most promising are cationic dendritic systems. However, the mode of action may vary among different strains due to variations in the lipid compositions of the membrane. Here, we investigated the interaction of two types of cationic imidazolium carbosilane dendrimers: one with a single cationic group (methyl imidazolium) and the other with the same cationic group but attached to a functional group (a pendant pyridyl moiety), capable of establishing interactions with membranes through H-bonding or ion–dipole electrostatic interactions. We used different models of the outer membrane of Gram-negative bacteria – Escherichia coli , Pseudomonas aeruginosa, and Acinetobacter baumannii. Additionally, we assessed the combined effect of the dendrimers and the antibacterial endolysin on P. aeruginosa. Our results show that the mechanism of action depends on the type of dendrimer and the lipid composition of the membrane. We also demonstrate that the alteration of membrane fluidity and permeability to endolysin by the methyl imidazolium and pyridyl imidazolium dendrimers may play a more significant role in antimicrobial activity compared to membrane damage caused by positively charged dendrimers. [ABSTRACT FROM AUTHOR]

We evidence the ferroelectricity of two isostructural magnetic coordination networks obtained from a chiral imidazolium dicarboxylate salt ((S, S)‐1,3‐bis(1‐carboxylethyl)imidazolium or [HL*]) and Gd3+ or Dy3+ ions in presence of oxalic acid (H2ox). The two compounds exhibit a chiral structure P1 and ferroelectric properties. The crystallographic study shows that the Dy based‐compound is isostructural to the Gd analog. The non‐centrosymmetry of the two samples was further checked by means of nonlinear optical spectroscopy. The room temperature ferroelectric character of the compounds has been investigated through by an original method, derived from that used for thin films, made possible by preparing the sample as thin slices of resin containing inclusions of the coordination compounds. [ABSTRACT FROM AUTHOR]

In the current study, the synthesis of an imidazolium ionic liquid (imi@MCM‐41/Fe3O4) was carried out with the aim of its application as an additive to enhance the electrochemical properties of anion exchange membranes. In heterogeneous membranes, resin particles act as functional groups, and the uniform distribution of these particles on the membrane surface and their amount have a significant effect on the electrochemical properties of the resulting membranes. Imidazolium groups can act as functional groups in anion exchange membranes. Therefore, the addition of an ionic liquid with imidazolium functional groups was carried out with the double aim of increasing the number of functional groups and obtaining a more uniform distribution of resin particles on the membrane surface. The FTIR and SEM analyses confirmed the functionalization of ionic liquid with imidazolium groups and their size on a nanometer scale. The effect of the ionic liquid to the resin ratio on the electrochemical properties and on the hydrophilicity of the membrane was investigated. The results showed that the uniform distribution of resin particles on the membrane surface in the presence of ionic liquid nanoparticles as well as the presence of ionic liquid functional groups significantly improved the electrochemical properties of the membrane. At a concentration of 1 wt.%, the ion exchange capacity, permselectivity, and electrical resistance were enhanced by 73%, 9%, and 47%, respectively. [ABSTRACT FROM AUTHOR]

Context: By using the DFT theory, the orbital energies of twenty-five ionic liquids were estimated. To comprehend their molecular stability and chemical reactivity, the orbital energy values, orbital energy gap (HOMO–LUMO energy gap), chemical hardness (η), chemical softness (S), electronegativity (χ), and electrophilicity index (ω) were computed. The interaction energies between all of the cations and anions under study were then computed and examined. Finally, using quantum chemical calculations, the molecular polarity of all 25 ionic liquids was examined using the sigma profile and sigma potential. Methods: Using the lowest orbital energy of the molecules, HF/6-31G* level of theory quantum chemical calculation were carried out using the MOLDEN and GAUSSIAN03 software. The B3LYP DFT approach produced a COSMO file that contained the species optimal SCD. [ABSTRACT FROM AUTHOR]

At temperatures ranging from 293.15 to 343.15 K and atmospheric pressure, the densities, refractive indices, dynamic viscosities, surface tensions, and sound speeds for [Cnmpyr][[NTf2] (n = 3,4,6,8), [Cnmpyr][[N(CN)2] (n = 3,4), [Cnmim][[N(CN)2] (n = 2,4) and [Bnzmim][[N(CN)2] were measured and discussed. As expected, all properties decrease as the temperature rises, with dynamic viscosity being the property most affected by the temperature change. Using linear correlation as a function of temperature, the density, speed of sound, surface tension, and refractive index are calculated, whereas the dynamic viscosity is correlated using the well-known Vogel–Fulcher–Tamman (VFT) equation. Using the experimental density data, the corresponding coefficients of thermal expansion were calculated. Furthermore, the Laplace–Newton equation was utilized to determine the isentropic compressibility. Results unveiled that the type of anions has the higher influence on the physical properties of the studied ionic liquids, while the elongation of the alkyl chain is less significant. [ABSTRACT FROM AUTHOR]

This study explores the electrochemical reduction of CO2 in dry acetonitrile containing 1,3‐dimethyl imidazolium cations, utilizing late‐transition metals (Au, Ag, Zn, Cu, and Ni). All metals exhibit remarkable selectivity, nearing 100 %, for CO formation. Particularly noteworthy is Au, which manifests the lowest (−2.37 V vs. Ag/Ag+) overpotential in chronopotentiometry experiments. We propose that, for metals with lower CO binding energies compared to Au (Ag and Zn electrodes) – calculated by DFT, the rate‐determining step is the adsorption of CO2. This distinction in CO2 adsorption is reinforced by the examination of partial charge transfer from negatively charged slabs to CO2 (−0.241 a.u with the Au electrode and +0.002 a.u with the Zn electrode). Conversely, the greater CO binding energy calculated for Cu and Ni likely diminishes electrocatalytic activity relative to the Au electrode. Our results unveil a volcano trend in catalyst activity, albeit with smaller performance disparities between the late‐transition metals and Au than previously observed in aqueous conditions, possibly due to the co‐catalytic influence of imidazolium cations. This study suggests that metals unsuitable for aqueous environments hold promise for cost‐effective and viable electrochemical conversion of CO2 to CO in non‐aqueous media containing imidazolium compounds. [ABSTRACT FROM AUTHOR]

1-Alkyl-3-methylimidazolium ionic liquids are common cellulose solvents and biomass pretreatment agents, while beta-irradiation ("e-beaming") is often used to decrease the recalcitrance of biomass towards hydrolysis or saccharification. Aiming at the general goal of elucidating the interaction between lignocellulosics, imidazolium-based ionic liquids, and beta-irradiation, we studied the effect of beta-irradiation on the pure ILs 1-ethyl-3-methylimidazolium and 1-butyl-3-methylimidazolium, both as chloride and acetate. Contrary to the expectation of inertness, irradiation caused degradation of the ILs, which was proportional to irradiation dosage, i.e., to irradiation time and intensity. At a dosage of 2400 kGy, 0.2% (2000 ppm) of the IL were chemically altered. The main degradation pathway is the formation of imidazole and N-methylimidazole with concomitant dealkylation. The cleaved-off alkyl groups, apparently in cationic form, react with the anions present, accounting for the formation of alkyl chlorides and alkyl acetates from the chloride ILs and acetate ILs, respectively. A second, minor pathway comprises the degradation of the imidazole ring under conversion of the C2-unit from the former C4-C5 moiety into ethylenediamine and reaction of the C1-unit from the former C2 with the IL anions. Because of the non-neglible byproduct formation, the degradation of the ILs upon beta-irradiation and possible side reactions of the resulting byproducts need to be kept in mind for all setups that involve beta-irradiation and imidazolium ILs simultaneously. [ABSTRACT FROM AUTHOR]

A polysubstituted 3-aminoimidazo[5,1-b]oxazol-6-ium framework has been accessed from a new nitrenoid reagent by a two-step ynamide annulation and imidazolium ring-formation sequence. Metalation with Au(I), Cu(I) and Ir(I) at the C2 position provides an L-shaped NHC ligand scaffold that has been validated in gold-catalysed alkyne hydration and arylative cyclisation reactions.

Abstract Unfortunately, oil reservoirs are complex considering the fluids (e.g., crude oil composition) and rock properties making it hard to propose a simple enhanced oil recovery (EOR) method for higher oil production. Besides, most of the investigations had focused on crude oil which is a complex mixture of thousands of components making it hard to extract any reliable conclusions with respect to the crude oil type. So, the current study is focused on the application of ionic liquids from different families of pyridinium and imidazolium, titanium oxide nanoparticles, and salts (MgCl2 and CaCl2) in the presence of resinous synthetic oil for the first time. The obtained results using the central composite design (CCD) approach revealed the positive effect of resin fraction on the IFT reduction by 27% considering the initial value (34.9%). Using the CCD approach revealed that using pH = 7, MgCl2 concentration = 21,000 ppm, CaCl2 concentration = 21,000 ppm, resin fraction of 9wt%t and 500 ppm of [C12mim][Cl] concentration reduces the IFT to minimum value of 0.62 mN/m while the minimum IFT value for optimum conditions of solution includes [C12py][Cl] led to minimum IFT value of 2.2 mN/m. But, the contact angle measurements revealed better synergy between [C12py][Cl] and TiO2-NPs (0–200 ppm) for better wettability alteration toward water-wet condition (27.3°) than [C12mim][Cl] (33.2°). Moreover, the IFT measurements revealed that the presence of TiO2-NPs is effective in reducing the IFT of the optimum formulations to 0.55 and 0.84 mN/m for [C12mim][Cl], and [C12py][Cl], respectively. According to the results, it seems that the obtained optimum formulations for [C12mim][Cl], and [C12py][Cl] are applicable for EOR purposes as new hybrid solutions.

Unfortunately, oil reservoirs are complex considering the fluids (e.g., crude oil composition) and rock properties making it hard to propose a simple enhanced oil recovery (EOR) method for higher oil production. Besides, most of the investigations had focused on crude oil which is a complex mixture of thousands of components making it hard to extract any reliable conclusions with respect to the crude oil type. So, the current study is focused on the application of ionic liquids from different families of pyridinium and imidazolium, titanium oxide nanoparticles, and salts (MgCl2 and CaCl2) in the presence of resinous synthetic oil for the first time. The obtained results using the central composite design (CCD) approach revealed the positive effect of resin fraction on the IFT reduction by 27% considering the initial value (34.9%). Using the CCD approach revealed that using pH = 7, MgCl2 concentration = 21,000 ppm, CaCl2 concentration = 21,000 ppm, resin fraction of 9wt%t and 500 ppm of [C12mim][Cl] concentration reduces the IFT to minimum value of 0.62 mN/m while the minimum IFT value for optimum conditions of solution includes [C12py][Cl] led to minimum IFT value of 2.2 mN/m. But, the contact angle measurements revealed better synergy between [C12py][Cl] and TiO2-NPs (0–200 ppm) for better wettability alteration toward water-wet condition (27.3°) than [C12mim][Cl] (33.2°). Moreover, the IFT measurements revealed that the presence of TiO2-NPs is effective in reducing the IFT of the optimum formulations to 0.55 and 0.84 mN/m for [C12mim][Cl], and [C12py][Cl], respectively. According to the results, it seems that the obtained optimum formulations for [C12mim][Cl], and [C12py][Cl] are applicable for EOR purposes as new hybrid solutions. [ABSTRACT FROM AUTHOR]

α‐Ketoaldehydes play versatile roles in the ubiquitous natural processes of protein glycation. However, leveraging the reactivity of α‐ketoaldehydes for biomedical applications has been challenging. Previously, the reactivity of α‐ketoaldehydes with guanidine has been harnessed to design probes for labeling Arg residues on proteins in an aqueous medium. Herein, a highly effective, broadly applicable, and operationally simple protocol for stapling native peptides by crosslinking two amino groups through diverse imidazolium linkers with various α‐ketoaldehyde reagents is described. The use of hexafluoroisopropanol as a solvent facilitates rapid and clean reactions under mild conditions and enables unique selectivity for Lys over Arg. The naturally occurring GOLD/MOLD linkers have been expanded to encompass a wide range of modified glyoxal‐lysine dimer (OLD) linkers. In a proof‐of‐concept trial, these modular stapling reactions enabled a convenient two‐round strategy to streamline the structure–activity relationship (SAR) study of the wasp venom peptide anoplin, leading to enhanced biological activities. [ABSTRACT FROM AUTHOR]

Abstract This study explores the electrochemical reduction of CO2 in dry acetonitrile containing 1,3‐dimethyl imidazolium cations, utilizing late‐transition metals (Au, Ag, Zn, Cu, and Ni). All metals exhibit remarkable selectivity, nearing 100 %, for CO formation. Particularly noteworthy is Au, which manifests the lowest (−2.37 V vs. Ag/Ag+) overpotential in chronopotentiometry experiments. We propose that, for metals with lower CO binding energies compared to Au (Ag and Zn electrodes) – calculated by DFT, the rate‐determining step is the adsorption of CO2. This distinction in CO2 adsorption is reinforced by the examination of partial charge transfer from negatively charged slabs to CO2 (−0.241 a.u with the Au electrode and +0.002 a.u with the Zn electrode). Conversely, the greater CO binding energy calculated for Cu and Ni likely diminishes electrocatalytic activity relative to the Au electrode. Our results unveil a volcano trend in catalyst activity, albeit with smaller performance disparities between the late‐transition metals and Au than previously observed in aqueous conditions, possibly due to the co‐catalytic influence of imidazolium cations. This study suggests that metals unsuitable for aqueous environments hold promise for cost‐effective and viable electrochemical conversion of CO2 to CO in non‐aqueous media containing imidazolium compounds.

This review examines the corrosion inhibition performance of ionic liquids used as corrosion inhibitors for aluminum, copper, magnesium, steel, and their alloys in various aqueous media. The predominant classes of ionic liquids employed are imidazolium, triazolium, thiazolium, phosphonium, pyridinium, ammonium, pyrrolidinium, and pyridinium-based ionic liquids. The pieces of literature revealed that the studies were carried out in acid, base, and salt media and an array of inhibition efficiencies was obtained. Herein, the possible influence of experimental techniques, ionic liquid concentration, ionic liquid structure, and molecular weight on the inhibition efficiency are tabulated and discussed.

Microenvironments tailored by multifunctional secondary coordination sphere groups can enhance catalytic performance at primary metal active sites in natural systems. Here, we capture this biological concept in synthetic systems by developing a family of iron porphyrins decorated with imidazolium (im) pendants for the electrochemical CO2 reduction reaction (CO2 RR), which promotes multiple synergistic effects to enhance CO2 RR and enables the disentangling of second-sphere contributions that stem from each type of interaction. Fe-ortho-im(H), which poises imidazolium units featuring both positive charge and hydrogen-bond capabilities proximal to the active iron center, increases CO2 binding affinity by 25-fold and CO2 RR activity by 2000-fold relative to the parent Fe tetraphenylporphyrin (Fe-TPP). Comparison with monofunctional analogs reveals that through-space charge effects have a greater impact on catalytic CO2 RR performance compared to hydrogen bonding in this context.

Lithium–sulfur (Li–S) battery features a high theoretical energy density, but the shuttle of soluble polysulfides between the two electrodes often results in a rapid capacity decay. Herein, a straightforward electrostatic adsorption strategy based on a cross‐linked polyimidazolium separator as a snaring shield of polysulfides is reported, which suppresses the undesirable migration of polysulfides to the anode. The porous ionic network (PIN)‐modified carbon nanotubes (CNTs) are successfully prepared and coated onto a commercial porous polypropylene membrane in a vacuum‐filtration step. The favorable affinity of the imidazolium ring toward polysulfide via the polar interaction and the electrostatic effect of ions mitigates the undesirable shuttle of polysulfides in the electrolyte, improving the Li─S battery in terms of rate performance and cycling life. Compared to the reference PIN‐free CNT‐coated separator, the PIN/CNT‐coated one has an increased initial capacity of 1.3 folds (up to 1394.8 mAh g−1 for PIN/CNT/PP‐3) at 0.1 C. [ABSTRACT FROM AUTHOR]

Several tetrahydroxidohexaoxidopentaborate(1-) salts of N-substituted diimidazolium cations or N-substituted dipyrrolidinium cations linked through N-C6-N chains have been synthesized and characterized spectroscopically (NMR, IR) and by single-crystal XRD studies: [R(NC3H3N)(CH2)6(NC3H3N)R][B5O6(OH)4]2·xH2O (R = Me, x = 0 (1); R = Et, x = 3 (2); [Me(NC3H3N)(CH2(C6H4)CH2)(NC3H3N)Me][B5O6(OH)4]2 (3), [(C4H8N)(R)(CH2)6(R)(NC4H8)][B5O6(OH)4]2·xB(OH)3 (R = Me, x = 0 (4, two polymorphs); R = Et, x = 0 (5); R = Bu, x = 4 (6); R = allyl, x = 0 (7)). Representative samples (1 and 7) were also characterized by thermal (TGA/DSC) studies; compounds are thermally decomposed to B2O3 in air. Numerous anion-anion H-bonding interactions are present in the solid-state structures of 1–5 and 7 as giant anionic networks. Unusually, in 6 there are no R22(8) anion-anion interactions as the co-crystallized B(OH)3 bridges between all pentaborate anions. H-bonding interactions in 1–7 have been examined using Etter graph set analysis; C(8), C33(18), R22(8), R22(12) and R44(12) motifs have been identified.

The processes of the sublimation and thermal decomposition of the 1-ethyl-3-methylimidazolium hexafluorophosphate ionic liquid (EMImPF6) were studied by a complex approach including Knudsen effusion mass spectrometry, IR and NMR spectroscopy, and quantum chemical calculations. It was established that the vapor over the liquid phase primarily consists of decomposition products under equilibrium conditions. Otherwise, the neutral ion pairs are the only vapor components under Langmuir conditions. To identify the nature of the decomposition products, an experiment on the distillation of the ionic liquid was performed and the collected distillate was analyzed. It was revealed by the IR and NMR spectroscopy that EMImPF6 decomposes to substituted imidazole-2-ylidene (C6N2H10PF5) and HF. The measured vapor pressure of C6N2H10PF5 reveals a very low activity of the decomposition products (−4) in the liquid phase. The absence of a significant accumulation of decomposition products in the condensed phase makes it possible to determine the enthalpy of sublimation of the ionic liquid assuming its unchanged activity. The thermodynamics of the EMImPF6 sublimation was studied by Knudsen effusion mass spectrometry. The formation enthalpy of EMImPF6 in the ideal gas state was found from a combination of the sublimation enthalpy and formation enthalpy of the ionic liquid in the condensed state. The obtained value is in good agreement with those calculated by quantum chemical methods.

CO2 emissions are constantly increasing, so it is necessary to continue working to mitigate the excess of CO2 in the atmosphere and reduce the effects it has on the environment. In this regard, we have developed novel catalysts by synthesizing ionic liquids based on imidazolium chloride, supported on hyper-crosslinked polymers (HCP-BzmimCl and HCP-Bis(BzmimCl)). These catalysts enable the highly selective N-formylation of secondary amines, utilizing CO2 as a carbon source, phenylsilane as a hydrogen donor, and DMF as a crucial polar additive. The reactions were carried out under mild conditions, with CO2 pressure at 5 bar and a temperature of 35ºC, yielding formamides in excellent yields. HCP-Bis(BzmimCl) has emerged as a particularly promising catalyst, boasting shorter reaction times, exceptional recyclability, and scalability for potential industrial applications.

We present an extension of our previously developed all-atom force field BILFF (Bio-polymers in Ionic Liquids Force Field) to three different ionic liquids: 1-ethyl-3-methyl-1,2,3-triazolium acetate ([EMTr][OAc]), 1-ethyl-3-methyl-1,2,3-triazolium benzoate ([EMTr][OBz]), and 1-ethyl-3-methylimidazolium benzoate ([EMIm][OBz]). These ionic liquids are of practical importance as they have the ability to dissolve significant amounts of cellulose even at room temperature. Our force field is optimized to accurately reproduce the strong hydrogen bonding in the system with nearly quantum chemical accuracy. A very good agreement between the microstructure of the quantum chemical simulations over a wide temperature range and experimental density data with the results of BILFF were observed. Non-trivial effects, such as the solvation shell structure and π – π stacking of the cations, are also accurately reproduced. Our force field enables accurate simulations of larger systems, such as solvated cellulose in different (aqueous) ionic liquids, and is the first to present the optimized parameters for mixtures of these solvents and water. [ABSTRACT FROM AUTHOR]

To explore novel hydrophilic groups of short‐chain fluorocarbon surfactants for aqueous film‐forming foam (AFFF), an original surfactant (S‐im) with a unique imidazolium structure was developed. The intermediate and S‐im were identified by FT‐IR and NMR, validating the mild synthesis route. MS spectrum correspondingly verified the molecular weight of S‐im (329.07). TGA analysis further revealed that S‐im showed satisfied thermal stability before 200 °C. Due to the synergism effect, equimolar S‐im/C6H13NaO3S (6.29 mmol/L) maintained a low surface tension of 17.81 mN/m. Likewise, the high surface activity of the equimolar mixture contributed to its spreading on different hydrocarbon fuels. We adjusted the mixture concentration to 20 mmol/L based on applicable standards to obtain a moderate foam expansion (9.7) and an opportune drained time (323 s). The mixture exerted a promising performance. All flames caused by investigated fuels were extinguished in 75 seconds, with burnback time exceeding 14 minutes, indicating a significant field application potential. [ABSTRACT FROM AUTHOR]

This research is based on the concept that mitochondria are a promising target for anticancer therapy, including thatassociated with the use of oxidative phosphorylation blockers (mitochondrial poisons). Liposomes based on L-α-phosphatidylcholine (PC) and cholesterol (Chol) modified with cationic surfactants with triphenylphosphonium (TPPB-n, where n = 10, 12, 14, and 16) and imidazolium (IA-n(OH), where n = 10, 12, 14, and 16) head groups were obtained. The physicochemical characteristics of liposomes at different surfactant/lipid molar ratios were determined by dynamic/electrophoretic light scattering, transmission electron microscopy, and spectrophotometry. The hydrodynamic diameter of all the systems was within 120 nm with a polydispersity index of no more than 0.24 even after 2 months of storage. It was shown that cationization of liposomes leads to an increase in the internalization of nanocontainers in pancreatic carcinoma (PANC-1) and duodenal adenocarcinoma (HuTu 80) cells compared with unmodified liposomes. Also, using confocal microscopy, it was shown that liposomes modified with TPPB-14 and IA-14(OH) statistically better colocalize with the mitochondria of tumor cells compared with unmodified ones. At the next stage, the mitochondrial poison rotenone (ROT) was loaded into cationic liposomes. It was shown that the optimal loading concentration of ROT is 0.1 mg/mL. The Korsmeyer–Peppas and Higuchi kinetic models were used to describe the release mechanism of ROT from liposomes in vitro. A significant reduction in the IC50 value for the modified liposomes compared with free ROT was shown and, importantly, a higher degree of selectivity for the HuTu 80 cell line compared with the normal cells (SI value is 307 and 113 for PC/Chol/TPPB-14/ROT and PC/Chol/IA-14(OH)/ROT, respectively) occurred. It was shown that the treatment of HuTu 80 cells with ROT-loaded cationic liposomal formulations leads to a dose-dependent decrease in the mitochondrial membrane potential. [ABSTRACT FROM AUTHOR]

A class of phenolphthalein anilide (PA)-based poly(ether sulfone) multiblock copolymers containing pendant quaternary ammonium (QA) and imidazolium (IM) groups were synthesized and evaluated as anion exchange membrane (AEM) materials. The AEMs were flexible and mechanically strong with good thermal stability. The ionomeric multiblock copolymer AEMs exhibited well-defined hydrophobic/hydrophilic phase-separated morphology in small-angle X-ray scattering and atomic force microscopy. The distinct nanophase separated membrane morphology in the AEMs resulted in higher conductivity (IECw = 1.3-1.5 mequiv./g, σ(OH-) = 30-38 mS/cm at 20 °C), lower water uptake and swelling. Finally, the membranes were compared in terms of microbial fuel cell performances with the commercial cation and anion exchange membranes. The membranes showed a maximum power density of ~310 mW/m2 (at 0.82 A/m2); 1.7 and 2.8 times higher than the Nafion 117 and FAB-PK-130 membranes, respectively. These results demonstrated that the synthesized AEMs were superior to Nafion 117 and FAB-PK-130 membranes.

• New surface active Tetracationic AImILs highly adsorbed 2.8 mol of CO 2 /mol. • Amphiphilic thermal stable porous spheres of CaCO 3 NPs prepared from CO 2. • Highly dispersed CaCO 3 NPs in seawater used as additive for WBD fluids. • CaCO 3 @ HDAP-ImA and CaCO 3 @DDAP-ImA particles employed as a viscosifier and/or filtrate control agent in bentonite- based WBMs. Conversion and capture of carbon pollutants based on carbon dioxide to valuable green oil-field chemicals are target all over the world for controlling the global warming. The present article used new room temperature amphiphilic imidazolium ionic liquids with superior surface activity in the aqueous solutions to convert carbon dioxide gas to superior amphiphilic calcium carbonate nanoparticles. In this respect, tetra-cationic ionic liquids 2-(4-dodecyldimethylamino) phenyl)-1,3-bis (3-dodecyldimethylammnonio) propyl) bromide-1-H-imidazol-3-ium acetate and 2-(4-hexyldimethylamino) phenyl)-1,3-bis(3-hexcyldimethylammnonio) propyl) bromide-1 H-imidazol-3-ium acetate were prepared. Their chemical structures, thermal as well as their carbon dioxide absorption/ desorption characteristics were evaluated. They were used as solvent and capping agent to synthesize calcium carbonate nanoparticles with controlled crystalline lattice, sizes, thermal properties and spherical surface morphologies. The prepared calcium carbonate nanoparticles were used as additives for the commercial water based drilling mud to improve their filter lose and rheology. The data confirm that the lower concentrations of 2-(4-dodecyldimethylamino) phenyl)-1,3-bis (3-dodecyldimethylammnonio) propyl) bromide-1-H-imidazol-3-ium acetate achieved lower seawater filter lose and improved viscosities. [ABSTRACT FROM AUTHOR]

The dynamical properties of four protic ionic liquids, based on the ethyltriazolium ([C 2 HTr 124 ]) and the ethylimidazolium ([C 2 HIm]) cation, were investigated. The associated anions were the triflate ([TfO]) and the bistriflimide ([TFSI]). Ionic conductivity values and self-diffusion coefficients were measured and discussed, extending the discussion to the concept of fragility. Furthermore, in order to allow the measurement of the ionic conductivity of very small volumes (<0.5 mL) of ionic liquid under an inert and dry atmosphere, a new setup was developed. It was found that the cation nature strongly affected the transport properties, the [C 2 HTr 124 ] cation resulting in slower dynamics than the [C 2 HIm] one. This was concluded from both conductivity and diffusivity measurements while for both properties, the anion had a lesser effect. By fitting the conductivity data with the Vogel–Fulcher–Tammann (VFT) equation, we could also estimate the fragility of these ionic liquids, which all fell in the range of very fragile glass-forming materials. Finally, the slower dynamics observed in the triazolium-based ionic liquids can be rationalized by the stronger interactions that this cation establishes with both anions, as deduced from the frequency analysis of relevant Raman signatures and density functional theory (DFT) calculations. [ABSTRACT FROM AUTHOR]

The degradation of an ionic liquid: hexyl methyl imidazolium chloride (HMImCl) in the systems of simulated solar light/ZnO and simulated solar light/ZnO/oxidant (i.e., H2O2 and S2O82−) were investigated in aqueous solution. The influences of different variables such as catalyst concentration, hydrogen peroxide, and persulfate dosage on HMImCl photocatalytic degradation were determined. It was found that the adsorption of HMImCl on the catalyst surface was insignificant. The photocatalytic degradation of HMImCl followed pseudo first‐order kinetics, and the rate constant at natural pH (pH 7.2) was 11.8 × 10−2 min−1. The addition of hydrogen peroxide to the process not only does not enhance the degradation rate of HMImCl but also decreases kapp significantly with [HMImCl] = 3×10−5 mol L−1, oxidant concentration (in the range of 5 × 10−5–10−1 mol L−1), and catalyst concentration of 1 g L−1. The results elucidated that the use of Na2S2O8 (in the range of 10−4–10−2 mol L−1) strongly enhances the degradation rate of HMImCl compared with photocatalytic process of the catalyst. [ABSTRACT FROM AUTHOR]

A comparative analysis is performed for the properties of two Fenton-type catalysts in the oxidation of sulfur-containing compounds with hydrogen peroxide and the desulfurization of crude oil. The catalysts are based on Cu(I) and Fe(III), and Mo(VI) and W(VI) polyoxometalates. Heterogeneous samples are imidazolium salts chemically immobilized on surfaces of silochrome and contain the iron and copper chloride complexes or phosphomolybdic and phosphotungstic acid anions. Thiophene (T), dibenzothiophene (DBT), methylphenyl sulfide (MPS), and a diesel fraction with an initial amount of sulfur of 1080 ppm are used as model substrates. It is found that the order of reactivity of thiophene substrates depends on the nature of metal-containing anions: thiophene > DBT on the Cu and Fe catalysts and DBT > thiophene on the polyoxometalate catalysts. This effect is explained using literature data. The catalyst based on phosphotungstic acid allows desulfurization of the diesel fraction of oil to amounts of sulfur of < 10 ppm, which meets today's environmental standards. [ABSTRACT FROM AUTHOR]

The processes of the sublimation and thermal decomposition of the 1-ethyl-3-methylimidazolium hexafluorophosphate ionic liquid (EMImPF6) were studied by a complex approach including Knudsen effusion mass spectrometry, IR and NMR spectroscopy, and quantum chemical calculations. It was established that the vapor over the liquid phase primarily consists of decomposition products under equilibrium conditions. Otherwise, the neutral ion pairs are the only vapor components under Langmuir conditions. To identify the nature of the decomposition products, an experiment on the distillation of the ionic liquid was performed and the collected distillate was analyzed. It was revealed by the IR and NMR spectroscopy that EMImPF6 decomposes to substituted imidazole-2-ylidene (C6N2H10PF5) and HF. The measured vapor pressure of C6N2H10PF5 reveals a very low activity of the decomposition products (<10−4) in the liquid phase. The absence of a significant accumulation of decomposition products in the condensed phase makes it possible to determine the enthalpy of sublimation of the ionic liquid assuming its unchanged activity. The thermodynamics of the EMImPF6 sublimation was studied by Knudsen effusion mass spectrometry. The formation enthalpy of EMImPF6 in the ideal gas state was found from a combination of the sublimation enthalpy and formation enthalpy of the ionic liquid in the condensed state. The obtained value is in good agreement with those calculated by quantum chemical methods. [ABSTRACT FROM AUTHOR]

The excellent catalytic activities of abnormal NHC carbene complexes, where the C2 position remains unaffected, and coordination occurs at the C4 or C5 position of the imidazolium ring, is still a fascinating but scarce area of research. This present work reports a palladium complex (LPdBr) bearing abnormal NHC with CNN pincer architecture. It is synthesized from imidazolium‐based quinoline ligand (LH) with Pd(OAc)2 via ‐NH and carbene deprotonation. The complex was fully characterized by NMR spectroscopy (1D and 2D) and high‐resolution mass spectrometry (HRMS). The structure and abnormal coordination modes of the complex are further confirmed with the help of single‐crystal X‐ray diffraction. The studies revealed the abnormal coordination mode in LPdBr where C5 carbon of the imidazolium ring participates in bonding, leaving the C2 position unaffected. The catalytic potential of complex LPdBr was investigated in the Pd‐catalyzed Suzuki‐Miyaura coupling of various aryl/heteroaryl chlorides with different aryl/naphthyl/phenanthryl boronic acids. The catalyst LPdBr successfully activated various less‐activated aryl chloride substrates. LPdBr also exhibited good catalytic activity at 1 mol% Pd loading under microwave irradiation and in green solvent water. The mechanism of the catalytic cycle is investigated and proposed by HRMS. [ABSTRACT FROM AUTHOR]

Recently, ionic liquids have been utilized to compatibilize polymer blends. In this brief review, two types of ionic liquids utilized as compatibilizing agents for polymer blends are described, namely imidazolium-based and phosphonium-based ionic liquids. Additionally, the preparation of polymer blends with different processes is presented. The effects of ionic liquids as compatibilizing agents on the chemical, mechanical, and thermal properties of polymer blends are also briefly reviewed. The information presented in this review contributes to a better understanding of the preparation of polymer blends compatibilized with ionic liquids and the crucial properties of polymer blends. [ABSTRACT FROM AUTHOR]

[Display omitted] The sonochemical exfoliation of graphite in solution has been demonstrated as a promising and easy technique for producing graphene dispersions. This is usually done in organic solvents and leads to unstable dispersions with very low graphene concentration. Ionic liquids (ILs) represent a versatile and safe alternative to traditional organic solvents. A few recent studies reported the use of commercial ILs with bulky anions, such as bis(trifluoromethylsulfonyl)imide, and aromatic cations, such as imidazolium, which favour the exfoliation of graphite through π-π and cation-π interactions. Although recently investigated, the role of aromatic groups on imidazolium cations is still controversial and systematic studies are still necessary. Besides, these studies were limited to liquid dispersions at room temperature. Herein, we prepared four highly aromatic imidazolium-based ILs, including the newly reported 1-(naphthylmethyl)-3-benzylimidazolium bis(trifluoromethanesulfonyl)imide, [(Np)(Bn)im][NTf 2 ]. These ILs were used for the sonochemical exfoliation of graphite and compared with a commercial benchmark, 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide [Bmim][NTf 2 ]. Interestingly, [(Np)(Bn)im][NTf 2 ] allowed reaching solid dispersions at room temperature containing thin few layer graphene sheets with long-term stability (up to 2 years) and high concentration (3.6 mg/mL). Such graphene dispersion combines long-term stability in the solid-state and high processability in the liquid state, by a simple heating above 60 °C. [ABSTRACT FROM AUTHOR]

Organotrifluoroborates have gained acceptance as radioprosthetic groups for radiofluorination. Of these, the zwitterionic prosthetic group "AMBF3" with a quaternary dimethylammonium ion dominates the trifluoroborate space. Herein, we report on imidazolium‐methylene trifluoroborate (ImMBF3) as an alternative radioprosthetic group and report on its properties in the context of a PSMA‐targeting EUK ligand that was previously been conjugated to AMBF3. The ImMBF3 is readily synthesized from imidazole and conjugated via CuAAC "click" chemistry to give a structure similar to PSMA‐617. 18F‐labeling proceeded in one step per our previous reports and imaged in LNCaP‐xenograft bearing mice. The [18F]‐PSMA‐617‐ImMBF3 tracer proved to be less polar (LogP7.4 = −2.95 ± 0.03) while showing a significantly lower solvolytic rate (t1/2 = 8100 min) and slightly higher molar activity (Am) at 174 ± 38 GBq/μmol. Tumor uptake was measured at 13.7 ± 4.8%ID/g and a tumor:muscle ratio of 74.2 ± 35.0, tumor:blood ratio of 21.4 ± 7.0, tumor:kidney ratio of 0.29 ± 0.14, and tumor:bone ratio of 23.5 ± 9.5. In comparison with previously reported PSMA‐targeting EUK‐AMBF3 conjugates, we have altered the LogP7.4 value, tuned the solvolytic half‐life of the prosthetic, and increased radiochemical conversion while achieving similar tumor uptake, contrast ratios, and molar activities compared with AMBF3 bioconjugates. [ABSTRACT FROM AUTHOR]

In this paper we report on the sol-gel synthesis of cobalt oxide in four different ionic liquids with two different cations and anions. The employed ionic liquids are; 1-ethyl-3-methylimidazolium trifluoromethylsulfonate ([EMIm]TfO), 1-butyl-1-methylpyrrolidinium trifluoromethylsulfonate ([Py1,4]TfO), 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide ([EMIm]TFSA), and 1-butyl-1-methylpyrrolidiniumbis(trifluoromethylsulfonyl)amide ([Py1,4]TFSA). The influence of the cation and anion of the ionic liquids on the morphology of the synthesized oxides was explored. The results showed that octahydron-shaped Co3O4 nanoparticles with different average sizes depending on the type of the employed ionic liquid. The imidazolium cation was found to play a significant role in reducing the particle size of the synthesized Co3O4 nanoparticles. The samples prepared in the imidazolium-based ionic liquids showed smaller particle sizes than those of the samples prepared in the pyrrolidinium-based ionic liquids. The shape of the particles of the synthesized Co3O4 was not affected by the type of the ionic liquids. Highlights: Co3O4 nanoparticles were obtained in the ionic liquids [EMIm]TfO, [Py1,4]TfO, [EMIm]TFSA and [Py1,4]TFSA via the sol–gel approach. Octahydron-shaped Co3O4 nanoparticles with different average sizes depending on the type of the employed ionic liquid were obtained. The imidazolium cation plays a significant role in reducing the particle size of the synthesized cobalt oxide. The type of the anion or cation of the employed ionic liquids does not show an obvious influence on the shape of the synthesized cobalt oxide particles. [ABSTRACT FROM AUTHOR]

To study the fluorescent behavior of quantitatively confined aggregation‐induced emission (AIE) molecules in a giant cavity, herein a new type of coordination‐driven cuboctahedron cage is presented, with 12 AIE molecules anchored endohedrally linked with different‐length alkyl chains. The cage with confined tetraphenylethylene molecules shows strong fluorescence in highly diluted conditions (4 × 10−7 m). The fluorescence quantum yield can be altered from 3.23% up to 81.37%, upon prolonging the length of alkyl chains to C16. The study shows a great potential application in biology mimic and fluorescent microscopes utilizing confined or isolated fluorescent methods. [ABSTRACT FROM AUTHOR]

In this paper, we report on the crystal structure of salt 1-(4-bromo-2,3,5,6-tetrafluorophenyl)-3-(3-phenylbenzyl)-4-methylimidazolium bromide, 3, synthesized by the sequential nucleophilic attack of 4-methylimidazole on bromopentafluorobenzene and then 3-phenylbenzyl bromide. The salt was characterized by 1H, 13C, and 19F NMR spectroscopy and mass spectrometry. [ABSTRACT FROM AUTHOR]

We present the first example of charged imidazolium functionalized porphyrin‐based covalent organic framework (Co‐iBFBim‐COF‐X) for electrocatalytic CO2 reduction reaction, where the free anions (e.g. F−, Cl−, Br−, and I−) of imidazolium ions nearby the active Co sites can stabilize the key intermediate *COOH and inhibit hydrogen evolution reaction. Thus, Co‐iBFBim‐COF‐X exhibits higher activity than the neutral Co‐BFBim‐COF, following the trend of F−

Ionic liquids (ILs), due to their specific properties, can play the role of persistent water contaminants. Fungi manifest the ability to decompose hardy degradable compounds, showing potential in the biodegradation of ILs, which has been studied extensively on sewage sludge; however, attention was drawn mainly to bacterial and not fungal species. The aim of the research was to determine the significance of fungi in ILs' biodegradation to extend the knowledge and possibly point out ways of increasing their role in this process. The research included: the isolation and genetic identification of fungal strains potentially capable of [OMIM][Cl], [BMIM][Cl], [OMIM][Tf2N], and [BMIM][Tf2N] degradation, adjustment of the ILs concentration for biodegradability test by MICs determination and choosing strains with the highest biological robustness; inoculum adaptation tests, and finally primary biodegradation by OECD 301F test. The study, conducted for 2 mM [OMIM][Cl] as a tested substance and consortium of microorganisms as inoculum, resulted in an average 64.93% biodegradation rate within a 28-day testing period. For the individual fungal strain (Candida tropicalis), the maximum of only 4.89% biodegradation rate was reached in 10 days, then inhibited. Insight into the role of fungi in the biodegradation of ILs was obtained, enabling the creation of a complex overview of ILs toxicity and the possibilities of its biological use. However, only an inoculum consisting of a consortium of microorganisms enriched with a selected strain of fungi was able to decompose the IL, in contrast to that consisting only of an individual fungal strain. [ABSTRACT FROM AUTHOR]

BACKGROUND: Recent works have shown how to develop methods with specific economic and environmental aspects; this is the main motivation for research on energy efficient processes and environmentally friendly materials for formaldehyde (HCHO) storage. One specific goal is to improve the adsorption capacity for HCHO by constructing closely contacted connections with absorbents. RESULTS: In this study, two ionic liquids (ILs), 1‐methylimidazole hydrogen sulfate [MIM][HSO4] and Imidazole hydrogen sulfate [IM][HSO4] as newly developed absorbents for HCHO storage are applied for the first time. Based on thermogravimetric analysis (TGA) and nuclear magnetic resonance (NMR) results, it is concluded that their exceptional capacity for storage of HCHO is 31.07 and 34.60 (g formaldehyde)⋅(mol ionic liquid)−1, respectively. In addition, to study the renewability of HCHO, the decomposition rates of the reaction products (as a function of decomposition time and decomposition temperature) were measured. The optimal kinetic model was selected to satisfy the formation and decomposition processes of the products. Thereafter, the activation energy (E), pre‐finger factor (A), decomposition rate constant of the decomposition reaction, and the rate constant of the reaction were determined. NMR results confirmed that the higher storage capacity of HCHO in [MIM][HSO4] and [IM][HSO4] is mostly attributed to the stronger covalent bonds between the ionic liquids (ILs) and HCHO. CONCLUSION: These ILs are, thus, promising candidates as adsorbents for the design of air depollution processes. This study may provide new insights into the use of ILs for storage of HCHO for low‐cost, high‐performance, and environmentally benign adsorbents for indoor air purification. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Dermabacter vaginalis is a human-derived bacterium isolated from vaginal fluid of a Korean female in 2016. Although several human-related species in Dermabacter genus have been reported there are few studies on their bioactive metabolites. Dermazolium A (1), a rare imidazolium metabolite, was isolated from D. vaginalis along with five known metabolites (2–6) and their chemical structures were determined by NMR, HRMS, and MS/MS data analysis. Feeding experiments using predicted precursors and biomimetic total synthesis of 1 corroborated its structure and led to suggestion of biosynthetic pathway of 1. Antibacterial tests on the isolated compounds showed that 1 is a mild antibacterial agent with MIC values of 41 µg/mL against methicillin-resistant Staphylococcus aureus (MRSA) USA300, Lacticaseibacillus paracasei subsp. paracasei KCTC 3510 and Brevibacterium epidermidis KCTC 3090. [ABSTRACT FROM AUTHOR]

The photovoltaic performance of inverted (positive‐intrinsic‐negative) perovskite solar cells (PSCs) is predominantly limited by interfacial recombination loss. Here, by constructing a low‐dimensional halide/perovskite heterostructure, non‐radiative recombination pathways at the perovskite/C60 contact are effectively eliminated and a voltage loss of only 370 mV is achieved in inverted PSCs. Through molecular engineering of the organic spacer, a strong electronic coupling is enabled at the heterointerface, which effectively shifts the gap states out of the bandgap and leads to a prolonged carrier lifetime of 4.28 µs. Our strategy enables a power conversion efficiency of 24.09% (certified 23.54%) for inverted PSCs with an open‐circuit voltage of 1204 mV, and an efficiency of 21.89% (certified 21.48%) for centimeter‐scale cells. The devices retain 92% of the initial efficiency after 85 °C thermal aging for over 1400 h, and 95% of the initial efficiency after 1008 h of maximum power point operation under AM1.5G illumination in air. [ABSTRACT FROM AUTHOR]

The applicability of the concept of structural depolymerization is demonstrated by the example of titanium(IV) fluoride and its complex salts obtained in the systems CsF/TiF4/aHF, (Gua)2CO3/TiF4/aHF, (Gua)Cl/TiF4/aHF, and Im/TiF4/aHF (aHF, anhydrous hydrogen fluoride; (Gua+), guanidinium cation, [C(NH2)3]+; Im, imidazole). The compositions of the fluoridotitanates(IV) formed in these systems and their crystal structures are considered in terms of the degree of polymerization (ε). The latter is defined as the ratio between the number of bridging fluorine atoms (M − Fb − M) and the number of terminal fluorine atoms (M − Ft) in the [MnF4n+x]x− (M = Ti; n ≥ 1) structural fragments. With increasing initial amount of fluoride ion donors (AX = CsF or in situ formed (Gua)F and ImHF) in AF/TiF4 reactions, the degree of polymerization of the crystal structures of the obtained salts decreases. [ABSTRACT FROM AUTHOR]