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Ionogel electrolytes (IGEs) with chemical and thermal stability properties have attracted considerable attention for all-solid-state energy storage devices, particularly for high-performance supercapacitors (SCs). However, achieving high conductivity, flexibility, and toughness, as well as deformation and impact resistance in special cases, is challenging with the typical polymer based on ionic liquids (ILs). Here, an effective gelation strategy is proposed for the preparation of free-standing LiTFSI/[EMIM][TFSI]/PVDF-HFP ionogels (IGs) by double-additive induced physical cross-linking. The mechanical and electrochemical properties of the IGs can be synergistically optimized by the cross-linking and entanglement of LiTFSI and [EMIM][TFSI] with the PVDF-HFP network. The target IGs simultaneously exhibit excellent deformation capacity (over 50 %), high ionic conductivity (10.3 × 10−3 S cm−1 at 25 °C), hardness (H: 728.6 kPa), and Young's modulus (E: 11.4 MPa), which can exhibit the specific capacitance of 274. 55 F g−1, energy density of 38.13 Wh kg−1 and maximum power density of 2499.93 W kg−1 in the fabricated symmetric supercapacitor. The results will motivate us to further explore their applications for flexible electronic devices, wearable electronic skin, and flexible energy storage. [Display omitted] • The IGE has excellent mechanical strength and deformation ability. • The IGE with high ionic conductivity of 10.5 × 10−3 S cm−1. • The supercapacitor provides higher specific capacitance, energy and power density. • The change of ionic conductivity was verified by molecular dynamics simulation. [ABSTRACT FROM AUTHOR]

• Two nitrile-functionalized ionic liquids mixture systems with γ–butyrolactone were prepared. • The densities and conductivities of two mixture systems were measured. • The excess molar volumes (V E) and apparent molar volumes (V ϕ), were calculated from the density data. • The behaviors of intermolecular interactions were explained by the volumetric properties changes, DSC analysis, IR spectrum shifts, and DFT calculations. Two functionalized ionic liquids, 1-cyanopropyl-3-methylimidazolium bistrifluoromethanesulfonimide ([C 3 CNmim][TFSI]) and 1-cyanopropyl-3-methylimidazolium trifluoromethanesulfonate ([C 3 CNmim][OTF]) were blended with γ-butyrolactone (GBL) under the full concentration range (molar fraction from 0 to 1) to form mixture systems, respectively. The densities and conductivities of pure ILs and their mixture systems were measured in the temperature range 288.15–343.15 K under normal pressure. The Vogel–Fulcher–Tammann (VFT) equation is employed to investigate the temperature dependence of conductivity. The volumetric properties of the mixture systems, excess molar volumes (V E) and apparent molar volumes (V ϕ), were calculated from the density data. The Redlich–Kister (R–K) polynomial equation and Redlich–Rosenfeld–Meyer (RRM) equation were used for the fittings of the V E and V ϕ , respectively. Further, the behaviors of intermolecular interactions in the mixture systems were explained by a combined analysis method composing of the assessment of the volumetric properties changes, the differential scanning calorimetry (DSC) analysis, the infrared (IR) spectrum shifts, and COSMO-RS methodology based on density functional theory (DFT) calculations. The stable optimized structures, H-bonding information, interaction energies, and charge distributions were consequently obtained. It can be found that the addition of the GBL weakened the hydrogen bonding interactions between the IL cations and anions. The [C 3 CNmim][TFSI] + GBL mixture system shows the lowest energy difference and it may give strong ion-solvent interactions when compare to [C 3 CNmim][OTF] mixture system. [ABSTRACT FROM AUTHOR]

Abstract: A new layered ammonium nickel(II) diphosphate, (NH4)2[Ni3(P2O7)2(H2O)2], has been synthesized ionothermally in the ionic liquid 1-butyl-3-methyl imidazolium bromide and characterized by powder X-ray diffraction, elemental analysis, scaning electron microscopy, thermogravimetry etc. The results of the characterization show that the crystal adopts the monoclinic space group P21/a with the lattice constants a=9.23529(2) Å, b=7.98489(2) Å, c=9.40772(2) Å, β=100.2608(2)° and Z=2. Its structure consists of chains of cis- and trans-edge-sharing [NiO6]-octahedra linked via [P2O7] units to form layers of [Ni3(P2O7)2(H2O)2]2− in the ab plane. Adjacent layers are separated in the c-direction by ammonium ions. [ABSTRACT FROM AUTHOR]

Abstract: An ionic liquid (IL) BMIZn3Cl7 has been synthesized by directly mixing zinc chloride and 1-butyl-3-methylimidazolium chloride (BMIC) with molar ratio 3/1 under dry argon atmosphere according to the procedure of Lecocq and Abbott. The density and surface tension of the ionic liquid were measured in the temperature range from 318.2 to 343.2±0.1K. The estimation of physico-chemical properties of BMIZn3Cl7 was carried out. The thermal expansion coefficient and surface entropy were derived from the experimental data. In terms of Glasser''s theory, the standard molar entropy and lattice energy of the ionic liquid were estimated. Using the methods of Kabo and Rebelo the molar enthalpy of vaporization of the ionic liquid, at 298K and at the hypothetical normal boiling point were estimated. According to the interstice model, the calculated thermal expansion coefficient is in the same order of magnitude as the experimental value. [Copyright &y& Elsevier]

Silicoaluminophosphate zeotype with LTA structure (SAPO-LTA) was prepared using ionothermal approach in commercial 1-ethyl-3-methyl imidazolium ([emim]+) ionic liquid. 1H→13C CP/MAS NMR, TGA and CHN elementary analysis results demonstrated that ionic liquid acted as single organic template occluded in pairs in each α cage of the structure. SAPO-LTA exhibited high structural stability after detemplation with excellent BET surface area and microporous volume. Silica content in the products increased with that in the initial reactants with a maximum of SiO 2 wt% lower than 5%. 29Si MAS NMR and NH 3 -TPD results further proved the incorporation of Si in the framework with improved acidity as compared with its aluminophosphate (AlPO) counterpart. SAPO-LTA was active in MTO reaction, showing higher butene and C 5+ product selectivity than that of SAPO-34 with CHA structure, and higher propene to ethylene and lower C 1 to C 4 alkane selectivity in comparison with that of high-silica LTA zeolite (LTA-HSZ). The deactivation of SAPO-LTA catalyst was due to the occlusion of bulky polyaromatic coke in the LTA structure, and could be perfectly recovered during three cycles of regeneration by high-temperature calcination. Image 1 • SAPO-LTA were ionothermally prepared in commercial [emim]+ ionic liquid. • Ionic liquid acted as single organic template occluded in pairs in each α cage of the structure. • The detemplated SAPO-LTA exhibited high structural stability with excellent texture property. • SAPO-LTA with improved acidity was active in MTO reaction showing unique product selectivity. • The deactivated SAPO-LTA could be perfectly recovered by high temperature calcination. [ABSTRACT FROM AUTHOR]

Gel-polymer electrolytes (GPEs) are of great interest to build high-performing rechargeable electrical double-layer capacitors (EDLCs) owing to the combination of good electrochemical properties and improved safety. Herein, we report a quasi-solid-state GPE for EDLCs from a mixture of the poly (vinylidene fluoride- co -hexafluoro propylene) (PVDF-HFP) and ionic liquid 1-ethyl-3-methylimidazole tetrafluoroborate ([EMIM][BF 4 ]), which avoids the leakage of liquid electrolyte and the low conductivity of common solid electrolyte. The intermolecular forces of GPE was characterized by in-situ infrared (IR) spectroscopy, and the interactions between ionic liquid and polymer were also analyzed. The prepared GPE was observed to be easily procurable, excellent transparency, high thermal safety (thermal stability up to 320 °C) and outstanding electrochemical properties at room temperature (wide electrochemical stability window of 3.91 V versus SS (SS being stainless steel foils) and high ionic conductivity of 6.9 × 10−3 S cm−1). The specific capacitance, the maximum specific energy, and the maximum specific power of the fabricated symmetrical supercapacitor had been determined to be 161.8 F g−1, 89.89 Wh kg−1, and 8 kW kg−1, respectively. Moreover, the EDLC shows extraordinary electrochemical behaviors and cyclic stability over up to 10 000 cycles at 25 °C with 86% capacitance retention under a current load of 2 A g−1. The experimental results indicate the excellent potential of the [EMIM][BF 4 ] ionic-liquid-based gel polymer electrolyte for EDLCs. [Display omitted] • The GPE has outstanding ionic conductivity and high thermal safety (up to 320 °C). • IL promotes the formation of molecular forces in the GPE by in-situ FT-IR and DFT. • The EDLC offers higher specific capacitance, specific energy and specific power. [ABSTRACT FROM AUTHOR]

• Two ether-functionalized ILs mixture systems were prepared and their thermodynamic properties were measured. • The excess molar volume and viscosity deviation were calculated and provided a microscopic information on the interactions. • DFT calculation found that C2–H of the cation exhibited the capability to form H-bonds with anion and solvents. • The molecular dynamics simulations presented a more robust H-bonds interaction between [MOEmim][TFSI] and GBL compared to ACN. Ether-functionalized ionic liquids (ILs) have a higher fluidity and are widely used in a variety of applications due to the introduction of the ether group. In order to better understand the relationship between properties and internal interactions of ether-based ILs, we prepared two ether-functionalized ILs 1–2-methoxyethyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)imide ([MOEmim][TFSI]) with acetonitrile (ACN) or γ -butyrolactone (GBL) mixture systems, and investigated the changes of their thermodynamic properties and internal interaction behaviors over the entire concentration range. First, the thermodynamic properties such as dynamic viscosity, density and electrical conductivity of the two mixture systems were measured from 288.15 K to 343.15 K. The excess molar volume (V E), and viscosity deviation (Δ η) were calculated by using the measured experimental density and dynamic viscosity data, which can provide microscopic information on the interactions. Further, the intermolecular interactions of the mixture systems were evaluated by density functional theory (DFT) calculations. The sigma–profile (σ –profile) provided insight into the hydrogen bonds (H-bonds) and molecular surfaces interactions. We also used molecular dynamics simulations (MD) to study ILs mixtures in many different solvent concentrations, thereby providing a microscopic and macroscopic characterization of fluid structure, molecular aggregation, and intermolecular forces. [ABSTRACT FROM AUTHOR]

Abstract In this study, two novel binary systems of ionic liquids (ILs) {1-cyanopropyl-3-methyl-imidazolium bis(fluorosulfonyl)imide ([C 3 CNmim][FSI]), or 1-cyanopropyl-3-methyl-imidazolium trifluoromethanesulfonate ([C 3 CNmim][CF 3 SO 3 ]) + acetonitrile (AN)} are prepared over the whole concentration. Densities (ρ), electrical conductivities (σ), dynamic viscosities (η), and surface tensions (γ) of pure ILs and two binary systems were measured at temperatures from 288.15 to 323.15 K at 101 kPa within the whole composition range. The thermodynamic parameters of pure ILs such as coefficient of thermal expansion (α), standard molar entropy (S 0), and lattice energy (U POT) were estimated. The excess molar volumes (V E) were obtained from the experimental densities and fitted to Redlich–Kister (R–K) polynomial equation. The dependence of the transport properties (viscosity and conductivity) on temperature can be described by the Vogel–Fulcher–Tamman (VFT) equation. In order to obtain information about interactions between AN molecules and selected ILs, the density functional theory (DFT) calculations combining the COSMO–RS methodology were employed. The hydrogen bonds formation between components of the mixtures was discussed from the calculation results and the variations in the infrared (IR) spectrum. Highlights • Two novel binary systems were prepared and the physicochemical properties were measured. • Excess properties were estimated to discuss intermolecular interactions. • The density functional theory calculations were employed. • The infrared spectrum comparisons were used to describe intermolecular interactions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Immobilization of ILs on Merrifield resin by covalent binding. [•] The morphology and surface shape of Merrifield resin were affected greatly by the immobilized ILs. [•] The immobilized ILs showed better percent sulfur removal (up to ⩾30%) than Merrifield resin. [Copyright &y& Elsevier]

Abstract: ImCl-silica gel (SG-ImCl) was prepared by directly immobilized [1-methylimidazole][Cl] (ImCl) onto silica gel (SG) using co-condensation of ionic liquid modified organosilane and tetraethoxysilane (TEOS) as silica source in strong acid condition. The properties of the samples were characterized by FTIR, elemental analysis, 29Si MAS NMR, SEM, BET. The results suggested that [1-methylimidazole][Cl] had been successfully immobilized on silica gel. The structure and morphology of SG-ImCl was varied with the content of ImCl. Moreover, SG-ImCl with suitable content of ImCl exhibited higher adsorption capacity than pure SG for a series of thiophenic sulfur compounds and could remove them from fuel. [Copyright &y& Elsevier]

Abstract: Gallophosphate (GaPO4) molecular sieves were ionothermally prepared in 1-alkyl-3-methyl imidazolium bromide ionic liquids (ILs) with alkyl chain length varying from 2 to 6 carbons for the first time. Three kinds of GaPO4 materials such as GaPO4-a, cloverite (denoted as CLO below) and GaPO4-LTA were obtained, and their structures and morphologies were characterized by powder and single crystal XRD, SEM and multi-nuclear NMR. In the case of 1-ethyl-3-methyl imidazolium bromide ionic liquid, large single crystals of GaPO4-LTA with well-defined octahedral morphology was obtained in both sealed (ca. 400μm in size) and open vessels (ca. 300μm in size). Ionothermal synthesis is an effective method for the preparation of large single crystal of molecular sieves. With the alkyl chain length of the ionic liquids increasing from 2 carbons to 6 carbons, the size of GaPO4-LTA decreased sharply. The organic template cations in the as-synthesized GaPO4-LTA crystals may have two different kinds of conformational structures. Fluorine plays a role of co-template along with organic cations of ILs in the synthesis of GaPO4-LTA and CLO, while only GaPO4-a was obtained in the absence of fluorine. The reaction temperature can also affect the structure of the final structure. In the reaction medium of 1-ethyl-3-methyl imidazolium bromide IL, GaPO4-LTA was obtained at 180°C, while CLO was obtained at 150°C. [Copyright &y& Elsevier]

Two novel ionic-liquid-based binary mixture systems of N,N-diethyl-N-(2-methoxyethyl)- N -methylammonium tetrafluoroborate ([DEME][BF 4), or N,N-diethyl- N -methyl-N-(2-methoxyethyl)ammonium bis(trifluoromethylsulfonyl)imide ([DEME][TFSI]) + γ-butyrolactone (GBL) are prepared over the whole concentration range (mole fraction from 0–1). Some important thermodynamic properties and parameters of the pure ILs and two systems were measured and calculated. The temperature dependences of the transport properties (viscosity and conductivity) were described by the Vogel–Fulcher–Tamman (VFT) equation. The excess molar volumes (V E) were obtained from the experimental densities and fitted to Redlich–Kister (R–K) polynomial equation. The DSC analysis, the shifts of the infrared (IR) spectrum, and COSMO–RS methodology based on DFT calculations were combined to explain the interaction information of GBL molecules and cations/anions of the selected systems. The stable optimized structures, interaction energies, and charge distributions were further obtained. Those maybe slight enlighten the application of similar mixture systems in future. • Two new binary systems ([DEME][BF 4 + GBL and [DEME][TFSI] + GBL were prepared and the physicochemical properties were measured. • Volumetric properties between [DEME][BF 4 or [DEME][TFSI] and GBL were investigated. • Spectroscopy (FT-IR) and Differential Scanning Calorimeter (DSC) technique were used to discuss the molecular interactions. • The intermolecular interactions were evaluated by DFT calculations. [ABSTRACT FROM AUTHOR]