Ionic Network Research Articles

Aqueous N-H acid bis(trifluoromethylsulfonyl) imide Solution - [C4mim][Tf2N] Ionic Liquid Biphasic System: an Original Investigation by Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance

Transfers of solutes from an aqueous solution to an ionic liquid and vice versa has been well studied for years. On the other hand, influence of transferred solutes on the ionic liquid's network is not yet evaluated. Therefore, we focus on the aqueous - ionic liquid biphasic system composed of two immiscible solutions containing N-H acid bis(trifluoromethylsulfonyl) imide and [C4mim][Tf2N] ionic liquid. After mixing and separation of the two phases, a part of water, H3O+, [Tf2N−] and H[Tf2N] anions are transferred into [C4mim][Tf2N] ionic liquid because H[Tf2N] has a salting in effect. The presence of this solutes might modify the local structure of [C4mim][Tf2N] ionic liquid. So far, our goal is to evaluate this structural change using several tools. For this, one dimensional 1H, 19F and Diffusion Ordered Spectroscopy Nuclear Magnetic Resonance were carried out on [C4mim][Tf2N] ionic liquid. We observed that some of water molecules are free and formed local microstructure as water pocket inside the ionic liquid network. The others are hydrogen bonded to [Tf2N−] anions as Tf2N−….H-O-D….Tf2N− for example. As long as the mole fraction of water in the ionic liquid remains less than or equal to that of [C4mim+] or [Tf2N−] the structure of the network is maintained. Free water moves at its own speed and bound water is an inclusion in the [C4mim][Tf2N] network. As soon as the mole fraction of the water is greater than that of [C4mim+] or [Tf2N−], the network of [C4mim][Tf2N] ionic liquid is gradually dislocated. Charged clusters composed with [C4mim+], [Tf2N−] and bond water are build and free water flow between them.

Design and fabrication of thermoplastic elastomer with ionic network: A strategy for good performance and shape memory capability

Smart elastomeric materials with outstanding performance and multifunctional properties are highly desirable for many potential applications. Here, strong shape memory materials were prepared based on poly(vinylidene fluoride)/carboxylated nitrile butadiene rubber (PVDF/XNBR) blends containing ionic crosslinks. The ionic clusters in the blends improved mechanical properties and elasticity of the shape memory blends. Interestingly, the elongation at break of this blend increased with rubber content without deterioration of tensile strength. A remarkable improvement of mechanical performance of the blends arose from the reinforcing cite and dynamic mobility of ionic clusters in XNBR matrix. The combination of blending and ionic cross-linking not only improved mechanical properties but also improved shape memory performance. The blends prepared in this work exhibited thermally triggered shape memory because both phases are responsible for shape fixity and recovery. As a consequence, the blends with high XNBR content showed high shape recovery (90%). Finally, this work provides an efficient approach to design new ionic crosslinked blends with excellent mechanical properties and shape memory properties.

Polymerized Ionic Networks Solid Electrolyte with High Ionic Conductivity for Lithium Batteries

The performance of classical lithium-ion technologies based on liquid electrolytes has made great advances in the last two decades, but safety issues are inevitable for batteries assembled with liquid electrolytes, which have intrinsic instability. In response to this issue, solid polymer electrolytes are developed in the lithium batteries field extensively for improving safety issues, as well as miniaturizing and enhancing the energy densities. Considering the great advantages of polymerized ionic networks, such as facile synthesis, high charge density, and high stability, two polymerized ionic networks (PDM-TFSI-1 and PDM-TFSI-2) with different polysubstituted benzene groups have been developed. The new type of polymerized ionic network with cross-linked structure was synthesized by the simple radical copolymerization of 2-(dimethylamino)ethyl methacrylate and methyl methacrylate monomers, then the copolymer (Mn = 14.5 kg mol−1) reacted with polysubstituted bromobenzene to form a cross-linked structure, and finally this was ion exchanged with bis(trifluoromethane)sulfonimide lithium salt (LiTFSI). The ionic networks filled with ionic liquid/LiTFSI mixture exhibit high ionic conductivity (1.0 × 10–4 and 1.9 × 10–4 S cm–1) and high decomposition potential (4.7 V vs Li/Li+) at 30 °C. The batteries were assembled by sandwiching the obtained polymer electrolytes between a LiFePO4 cathode and a lithium anode, exhibiting good cycling stability and specific capacity, suggesting that these novel kinds of solid polymer electrolyte are promising for application in next-generation lithium-ion batteries.

Elucidating the Molecular Mechanisms for the Interaction of Water with Polyethylene Glycol-Based Hydrogels: Influence of Ionic Strength and Gel Network Structure.

The interaction of water within synthetic and natural hydrogel systems is of fundamental importance in biomaterial science. A systematic study is presented on the swelling behavior and states of water for a polyethylene glycol-diacrylate (PEGDA)-based model neutral hydrogel system that goes beyond previous studies reported in the literature. Hydrogels with different network structures are crosslinked and swollen in different combinations of water and phosphate-buffered saline (PBS). Network variables, polyethylene glycol (PEG) molecular weight (MW), and weight fraction are positively correlated with swelling ratio, while “non-freezable bound water” content decreases with PEG MW. The presence of ions has the greatest influence on equilibrium water and “freezable” and “non-freezable” water, with all hydrogel formulations showing a decreased swelling ratio and increased bound water as ionic strength increases. Similarly, the number of “non-freezable bound water” molecules, calculated from DSC data, is greatest—up to six molecules per PEG repeat unit—for gels swollen in PBS. Fundamentally, the balance of osmotic pressure and non-covalent bonding is a major factor within the molecular structure of the hydrogel system. The proposed model explains the dynamic interaction of water within hydrogels in an osmotic environment. This study will point toward a better understanding of the molecular nature of the water interface in hydrogels.

Ionic liquid-based semi-interpenetrating polymer network (sIPN) membranes for CO2 separation

This work explores the preparation of ionic liquid (IL)-based semi-interpenetrating polymer network (sIPN) membranes composed of poly(ethylene oxide) (PEO) network and linear nitrile butadiene rubber (NBR), incorporating up to 66 wt% of three ILs with a common cation ([C2mim]+) and different anions ([C(CN)3]–, [NTf2]– and [FSI]–). All sIPN/IL membranes were characterized by Fourier-transform infrared (FT-IR) spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and puncture tests. Ideal CO2/N2 and CO2/H2 separation performances of the prepared sIPN/IL membranes were investigated at T = 20 °C and 35 °C, respectively, and 1 bar of feed pressure. The incorporation of both [C2mim][NTf2] and [C2mim][FSI] ILs allowed to obtain sIPN/IL membranes with higher IL contents (66 wt%) compared to previously reported PIL–IL membranes with similar IL structures (40 wt%). The membranes containing [NTf2]– and [C(CN)3]– anions showed improved thermal stability compared to the neat PEO/NBR sIPN, being thermally stable up to 300 °C. Although sIPN/IL membrane mechanical properties were affected by the incorporation of IL, all membranes revealed high elongation properties (elongation upon puncture = 68–170%), mainly due to the presence of NBR component in the sIPN structure. The highest CO2/N2 permselectivity was obtained for the sIPN/66 wt% [C2mim][C(CN)3] membrane, while the sIPN/66 wt% [C2mim][FSI] membrane revealed the highest CO2 and N2 permeabilities. The incorporation of 66 wt% of [C2mim][FSI] into the sIPN also showed superior CO2/H2 separation performance, with a CO2 permeability of 727 Barrer and a CO2/H2 permselectivity of 10.9.

Improved antibacterial and mechanical performances of carboxylated nitrile butadiene rubber via interface reaction of oxidized starch

To fabricate antibacterial activity and simultaneous strengthened and toughened carboxylated nitrile butadiene rubber (XNBR) composites, starch was oxidized by H2O2 to achieve oxidized starch (OST) with different carboxyl content, meanwhile, ZnO were utilized to promote the in-situ interfacial reaction for improving compatibility of starch and XNBR. The formation of ionic cross-link networks and “Zinc-carboxylate polymers” in the XNBR/OST/ZnO composites were confirmed by FT-IR, XRD, XPS, SEM-EDS and TEM. Interestingly, because of the carboxyl groups of OSTs which provided a low pH surroundings to inhibit the growth of bacteria, XNBR/OST/ZnO composites achieved a significant antibacterial activity. Noteworthy, the sulfur-free XNBR composites achieved 3.04 and 1.99 times increase for tensile strength and elongation at break compared with neat XNBR. The mechanism of simultaneous strengthened and toughened for composites had been proposed. These new sustainable, green and facile fabricated XNBR/OST/ZnO could be utilized as the medical protective appliance to against the bacteria.

Amorphous Dual‐Layer Coating: Enabling High Li‐Ion Conductivity of Non‐Sintered Garnet‐Type Solid Electrolyte

AbstractGarnet‐type oxide Li6.4La3Zr1.4Ta0.6O12 (LLZTO) has attracted considerable attention as a highly promising solid state electrolyte. However, its high ionic conductivity is achievable only after high temperature sintering (≈1200 °C) to form dense pellets but with detrimental brittleness and poor contact with electrodes. Herein, a novel strategy to achieve high Li+ ion conductivity of LLZTO without sintering is demonstrated. This is realized by ball milling LLZTO together with LiBH4, which results in a LLZTO composite with unique amorphous dual coating: LiBO2 as the inner layer and LiBH4 as the outer layer. After cold pressing the LLZTO composite powders under 300 MPa to form electrolyte pellets, a high Li+ ion conductivity of 8.02 × 10–5 S cm–1 is obtained at 30 °C, which is four orders of magnitude higher than that of the non‐sintered pristine LLZTO pellets (4.17 × 10–9 S cm–1). The composite electrolyte displays an ultrahigh Li+ transference number of 0.9999 and enables symmetric Li–Li cells to be cycled for 1000 h at 60 °C and 300 h at 30 °C. The significant improvements are attributed to the continuous ionic conductive network among LLZTO particles facilitated by LiBH4 that is chemically compatible and electrochemically stable with Li metal electrode.

Structure, Molecular Interactions, and Dynamics of Aqueous [BMIM][BF4] Mixtures: A Molecular Dynamics Study.

Molecular dynamics simulations with many-body polarizable force fields were carried out to investigate the thermodynamic, structural, and dynamic properties of aqueous solutions of 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]). The radial distribution functions exhibit well-defined features, revealing favored structural correlations between [bmim]+, [BF4]-, and H2O. The addition of water is shown to alter ionic liquid structural organizations by replacing counterions in the coordination shells and disrupt the cation-anion network. At low water concentration, the majority of water molecules are isolated from each other and have lower average dipole moment than that in pure water. With increasing hydration level, while [bmim][BF4] ionic network breaks up and becomes isolated ion pairs or free ions in the dilute limit, water begins to form clusters of increasing sizes and eventually forms a percolating network. As a result, the average water dipole moment increases and approaches its bulk value. Water is also observed to have a substantial influence on the dynamics of ionic liquids. At low water content, the cation and anion have similar diffusion coefficients due to the correlated ionic motion of long-lived ion pairs. As the water concentration increases, both ions exhibit greater mobility and faster rotations from the breakup of ionic network. Consequently, the ionic conductivity of [bmim][BF4] aqueous solutions rises with increasing water composition.

Facile synthesis of CNTs@TiO2 composites by solvothermal reaction for high-rate and long-life lithium-ion batteries

Multi-walled carbon nanotubes (CNTs)@TiO2 composites with different contents of CNTs were prepared by employing solvothermal process using ethanol-glycerol mixture as solvent and subsequent calcination. The role of glycerol during solvothermal process was discussed and the microstructures of the as-prepared CNTs@TiO2 composites were characterized by scanning electron microscopy, high-resolution transmission electron microscopy and X-ray diffraction. The results indicate glycerol is one of the solvothermal reactants and also play an important role for the coating of TiO2 particles on the surface of CNTs because of its high viscosity. Moreover, with the increasing of the content of CNTs in composites, the surface areas of composites increase and TiO2 layer becomes more uniform. Notably, CNTs@TiO2 composites with 42 wt% CNTs have a specific surface area of 265.7 m2 g−1, and exhibit excellent high-rate performance and cyclic stability. Their specific capacities at 1C, 2C, 5C, 10C, 20C, 30C and 40C are 248, 228, 225, 212, 200, 194 and 191 mAh·g−1, respectively. Even at 50C and 60C, their specific capacities are still as high as 187 and 184 mAh·g−1, respectively. Moreover, 90.1% of the reversible capacity is retained after 1000 cycles at 10C. The excellent performance can be ascribed to the electronic and ionic rapid conductive network formed by CNTs in composites and the synergistic contribution from pseudocapacitance.

Cation–dipole interaction that creates ordered ion channels in an anion exchange membrane for fastOH−conduction

AbstractPrecise control over polyelectrolyte architecture, engineered for self‐assembly of ion‐conducting channels, is of fundamental and technological importance to many fields, for example, fuel cells and redox flow batteries and electrodialysis. Building on recent advances with the supramolecular chemistry, we introduce inter/intra‐molecular cation–dipole interactions between pendent quaternary ammoniums cations and polar polyethylene glycol grafts in an anion‐exchange membrane (AEM). Such interactions lead to desirable, ordered ion‐conducting pathways when in the membrane form. Comparison of the results of molecular dynamics simulation with1H NMR and nano‐scale microscopy analyses show that the cation–dipole interactions enhance self‐assembly and the formation of interconnected ionic network domains, providing three‐dimensional pathways for both water and ion transport. The resultant AEM exhibits high OH−conductivity (49 mS cm−1at 30°C) and a completive peak power density of 622 mW cm−2at 70°C when tested in a H2/O2single‐cell alkaline membrane fuel cell.

Microscopic Understanding of the Ionic Networks of “Water-in-Salt” Electrolytes

“Water-in-salt” electrolytes with excellent electrochemical and physical properties have been extensively investigated. However, the structural understanding of the lithium bis(trifluoromethane sulfonyl)imide (LiTFSI) in water is still lacking. Here, we perform synchrotron X-ray scattering to systemically study the structural variation of TFSI anions in an aqueous solution under a variety of concentrations and temperatures. There are two different solvation structures in the solution: TFSI - solvated structure and TFSI - network. As the concentration increases, the TFSI - solvated structure gradually disappears while the TFSI - network gradually forms. Even at relatively low concentrations, the TFSI - network can be observed. Our experimental results show that these two structures can coexist at a particular concentration, and temperature changes will lead to one structure’s formation or disappearance. Also, the TFSI - network is the key to obtain a stable electrochemical window under relatively high temperatures.

Hydration, Ion Distribution, and Ionic Network Formation in Sulfonated Poly(arylene ether sulfones)

We use molecular dynamics simulations to probe hydration, ion spacing, and cation-anion interaction in two sulfonated polysulfones with different ion distributions along the polymer backbone. At room temperature, these polymers remain in a glassy state even with water contents more than 10%. At the equilibrium water uptake, the ions exhibit a similar level of hydration as they would in their saturated aqueous solution. The framework of Manning's limiting law for counterion condensation is used to examine ionic interactions in the simulated polysulfones. The dielectric constant that the ions experience can be well approximated by a volume-weighted average of the dielectric constants of the polymer backbone and water. Our results show that a reasonable estimate of the average inter-ion distance, b, is obtained by using the distance where the sulfonate-sulfonate coordination number reaches 1. The spacing of the sulfonate ions along the polysulfone backbone plays a role in determining their spatial distribution inside the hydrated polymer. As a result, the value of b is slightly larger for polymers where the sulfonate ions are more evenly spaced along the backbone, which is consistent with experimental evidence. The simulations reveal that the sulfonate ions and sodium counterions form fibrillar aggregates at water contents below the equilibrium water uptake. Such extensive ionic aggregates are expected to facilitate ion transport in sulfonated polysulfone membranes, without the need for long-range chain motion as in the case of traditional rubbery ionic polymers. Our estimates for the dielectric constant and b are used in conjunction with Manning's theory to estimate the fraction of counterions condensed to the fixed ions. The prediction of Manning's theory agrees well with the simulation result.

Development of 3D bioprinted GelMA-alginate hydrogels with tunable mechanical properties

3D bioprinting is gaining attention as a biofabrication technique due to its potential to recreate the complex structure of native human tissue, combining high precision additive manufacturing, biocompatible inks, cells and biochemical factors. In this work, we evaluated the combination of covalent and ionic crosslinking networks as a strategy to modulate the properties of hydrogel inks and stripe-pattern printed structures to induce anisotropic mechanical properties. We found that for optimum printing, gelMA-alginate concentrations should be between 11 and 15% w/v and the polymer ratio and concentration modulate the rheological and compressive moduli of hydrogels. Furthermore, degradation and swelling rates are also adjustable, with some blends showing less than 20% degradation and negligible swelling over a 14 days period. Sheep adipose derived stem cells were included in three formulations and cell viability was >75% after bioprinting in all hydrogels. Stripe-patterned hydrogels were successfully printed using a dual printhead allowing us to modify the mechanical properties of 3D printed hydrogel scaffolds in each axis. The printed structure with gelatin (10% w/v) and gelMA-alginate (8% w/v - 7%w/v) hydrogel stripes showed a noticeable anisotropic mechanical behaviour. Thus, we demonstrated that chemical and structural factors could modulate the properties of printed biocompatible hydrogels, including anisotropic mechanical behaviour, with potential application in tissue engineering.

Gel–Polymer Electrolytes Based on Poly(Ionic Liquid)/Ionic Liquid Networks

The use of electrically charged, polymerized ionic liquids (polyILs) offers opportunities for the development of gel–polymer electrolytes (GPEs), but the rational design of such systems is in its i...

Three-Dimensional Printed Hydrogels with High Elasticity, High Toughness, and Ionic Conductivity for Multifunctional Applications.

Hydrogels have drawn extensive attention due to their unique physical and biological properties. However, the relatively low mechanical strength and poor processability of hydrogels limit their applications. Especially, the emerging 3D printing technology for nontoxic hydrogels requires proper formability and controllable mechanical behaviors. In this study, a new strategy to construct a novel double-network biocompatible hydrogel from poly(ethylene glycol) diacrylate (PEGDA) and short-chain chitosan (CS) via ionic-covalent cross-linking is by a two-step method involving UV curing followed by immersion in an anionic solution. The CS-based ionic network and PEGDA-based covalent network as well as the hydrogen bonds between them jointly induce excellent mechanical properties, which can be regulated by changing the PEGDA/CS content and ionic cross-linking time. Compared with conventional hydrogels, this mechanically optimized hydrogel exhibits a superior elastic modulus (3.84 ± 0.4 MPa), higher tensile strength (7.23 ± 0.2 MPa), and higher tensile strain (162 ± 7%). Notably, its excellent printing capability through the citrate anionic solution adjustment enables 3D printing with precision, flexibility, and a complex inner structure by extrusion in air at room temperature. In addition, a number of citrate ions existed in the ionic network, giving the hydrogels good electrical conductivity. Therefore, this printable, conductive, and tough hydrogel exhibits potential for vascular engineering, cartilage tissue engineering, and wearable device applications.

Intrinsic room temperature self-healing natural rubber based on metal thiolate ionic network

An intrinsic self-healing natural rubber featuring reversible metal-thiolate ion networks was fabricated and the corresponding healing mechanism and mechanical properties were presented. The developed materials were able to repair themselves at room temperature upon damage without any external stimuli. Reversible metal-thiolate ion networks were proven to form within the rubber material. These networks dominated the cross-linking system and were identified by Differential Scanning Calorimetry (DSC) and Fourier-transform Infrared Spectroscopy (FTIR). Meanwhile, the quantitative amount of metal-thiolate ion networks and covalent crosslinks was determined by swelling testing. Scanning Electron Microscopy (SEM) results revealed that intermolecular diffusion had occurred at the fracture area of the self-healing samples. The results revealed that the mechanical properties could be 100% regenerated after the broken samples were brought into contact with each other. It was also found that self-healing increased by 60% of the material lifespan. This new material is expected to open up promising avenues for the manufacturing of sustainable rubber products.

Ionic Percolation Networks in Composite Electrodes for All-Solid-State Batteries

Solid-state composite electrolytes made of polymers and ceramics can balance the need for high ionic-conductivity and mechanical flexibility in constructing all-solid-state lithium batteries. Although the interface of solid composite electrolytes and Li-metal anodes have been well studied, the ionic conduction through the interface with porous electrodes has not received the same level of attention. In this study, we fabricated ion-conductors used as both flowable gel-like ionic fillers and stiff ion-conducting separators to address interfacial ionic conduction challenges with porous electrodes. A composite electrolyte made of Li6.4La3Zr1.4Ta0.6O12 (LLZTO) and a poly(ethylene oxide) (PEO)-lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) matrix was chosen as a model system to study interfacial ionic conduction properties. This solid composite electrolyte exhibits a room temperature ionic conductivity of 1.2×10-4 S cm-1. The bulk moduli of these ionic conductors were adjusted by varying polymer molecular weight, filler content, and salt concentration. In order to minimize the impact of porosity induced interfacial impedance on the overall cell performance, an ionic percolation network within the electrode pores was created using flowable ionic filler. We built symmetric cells that are made of cathodes or ionically percolated cathodes to determine the impact of having ionic fillers on the interfacial impedance of porous electrodes. In conclusion, ionic conductors filled solid-state battery cells with zero porosity promise a reduction in the interfacial impedance of the composite electrode.

Composite Electrolyte Composed of Li1.5Al0.5Ti1.5(PO4)3 and PVDF-Based Gel Electrolyte Containing Highly Concentrated Electrolytes

Li ion conducting inorganic solid electrolytes have been widely investigated because of their high thermal stability and single-ion conducting property. Recently, some of inorganic solid electrolytes were found to have high ionic conductivity in the order of 10-3−10-2 S/cm at room temperature, which are comparable to that of conventional liquid electrolytes. The use of a Li metal anode, which has a high specific capacity, can significantly increase the cell energy density. However, most of the inorganic solid electrolytes are known to be thermodynamically unstable against Li metal and form the decomposition phases, which cause high interfacial resistance between electrode | electrolyte and degrade the cell performance. Surface roughness and brittleness of inorganic solid materials, which make the poor interfacial contact, are known to cause the increase in the interfacial resistance between electrode and electrolyte. To address these issues, much effort has been devoted to developing composite electrolytes combining inorganic solid electrolytes with polymer electrolytes. Poly(ethylene oxide) (PEO) is often used in fabricating composite electrolytes because of its advantageous characteristics such as processability, flexibility and Li ion solvation ability. However, there are intrinsic problems such as low Li transference number of ~0.2, low ionic conductivity in the order of 10-5 mS/cm at room temperature, and poor oxidative stability. Polymer gel electrolytes composed of ionic liquids and polymer network are self-standing and flexible while inheriting the properties of ionic liquids such as high ionic conductivity, electrochemical stability, and nonflammability.In the present study, we prepared a flexible composite electrolyte by combining a NASICON type Li1.5Al0.5Ti1.5(PO4)3 (LATP) fillers and a polymer gel electrolyte. The gel electrolyte was composed of poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) and a liquid electrolyte of LiN(SO2CF3)2 (LiTFSA)/sulfolane (SL). The molar ratio of [LiTFSA]/[SL] was controlled to be 1/2. The gel electrolyte (without LATP) was prepared by a solution casting method, and the obtained gel was flexible. The electrochemical properties of the gel electrolyte are comparable to that of the liquid electrolyte of [LiTFSA]/[SL] = 1/2, which has a relatively high transference number of ~0.64. The composite electrolytes composed of the gel and LATP mixed in various ratios were prepared. The solid-state 6Li magic-angle spinning (MAS) NMR measurements revealed that the Li ion exchange reaction occurred at the interface between LATP and the gel electrolyte, suggesting that both LATP and gel phases contribute to the Li ion conduction in the composite electrolytes. However, AC impedance measurement for the interface between LATP and gel electrolyte suggested that the resistance for the Li-ion transfer at the interface causes the increase in resistance of the composite electrolyte, resulting in the decrease in ionic conductivity. We will present the effects of the LATP/gel electrolyte interface on the physicochemical properties of the composite electrolyte such as ionic conductivity and Li-ion transference number. We will report the charge-discharge performance of lithium batteries using the composite electrolytes.

Processable hypercrosslinked ionic networks for effective removal of methyl orange

Synthesis of adsorbents with permanent micro/mesoporous structures, tunable functional groups and processability is of great interest in industrial-scale processes for treating dye wastewater. Herein, a feasible crosslinking method has been employed to prepare porous ionic polymers (imidazolium and pyridinium-based) as adsorbents. The obtained materials have been utilized for the removal of methyl orange from aqueous solution and the maximum capacities of imidazolium-based adsorbents reached up to 1159 mg/g, which is superior to those of pyridinium-based ones and most known porous sorbents. The binding energies drawn from theoretical calculations based on density functional theory (DFT) proven the strong interactions between ionic units and dyes. Furthermore, freestanding porous membranes were fabricated from the adsorbents successfully by a step-by-step cross-linking process, implying their great potential in practical anionic dye removal.

In Situ Polymerized Methacrylate Based Electrolyte for Lithium‐Ion Batteries

AbstractWe propose a novel approach for incorporating a polymer electrolyte into lithium‐ion batteries by employing a pre‐polymer electrolyte (PPE). The PPE consists of a conventional carbonate‐based electrolyte that also contains 2‐(trimethylsilyloxy)ethyl methacrylate (TSEMA) as a monomer and 2,2′‐azobis(2‐methylpropionitrile) (AIBN) as an initiator; this combination can form a gel‐type polymer electrolyte after being subjected to an aging process. The results confirm that aging the PPE at 45 °C leads to the successful formation of a gel‐type polymer in the cell through an in‐situ polymerization reaction. The in‐situ‐formed gel‐type polymer electrolyte demonstrates relatively low ionic conductivity compared to conventional electrolytes, but it can still be used in lithium‐ion batteries, since an ionic network is well developed on the electrode. The combination of lithium titanium oxide anode materials and this in‐situ‐formed gel‐type polymer electrolyte is compatible with high temperatures, as the cell cycled with the methacrylate‐based in‐situ‐formed electrolyte exhibits stable cycling retention after 50 cycles.