竹岡 裕子

S-6X multi-block copolymers can be developed by direct one-pot copolymerization via Ni(0) coupling reaction, allowing high conductivity and strength on a wide-range of IECs.

Ionic plastic crystals (IPCs) have been studied as solid-state proton conductors due to their properties such as non-volatility, plasticity, and high ionic conductivity. In order to further improve their proton transport property, understanding the relationship between the ion structure and the properties of IPCs is needed. For this purpose, five pyrrolidinium salts with dihydrogen phosphate anion ([DHP]−) were synthesized. 1-Ethyl-1-methylpyrrolidinium ([C1,2pyr]+) cation and 1-(2-hydroxyethyl)-1-methylpyrrolidinium ([C1,2OHpyr]+) cation exhibited one or more solid-solid phase transitions in DSC traces. The 1H and 31P solid state NMR results indicated that the component ions in [C1,2pyr][DHP] exhibited rotational mobility in Phase I. [C1,2pyr][DHP] and [C1,2OHpyr][DHP] exhibited higher ionic conductivity values than the other pyrrolidinium salts after the addition of H3PO4, and their ionic conductivity was over 10−3 S cm−1 at 120 °C. Thus, rotational mobility and the hydroxyl group on the pyrrolidinium cation will contribute to proton transport in the solid-state phases.

A few kinds of thermoresponsive diblock copolymers have been synthesized and utilized for palladium-catalyzed coupling reactions in water. Poly(N-isopropylacrylamide) (PNIPAAm) and poly(N,N-diethylacrylamide) (PDEAAm) are employed for thermoresponsive segments and poly(sodium 4-styrenesulfonate) (PSSNa) and poly(sodium 2-acrylamido-methylpropanesulfonate) (PAMPSNa) are employed for hydrophilic segments. Palladium-catalyzed Mizoroki–Heck reactions are performed in water and the efficiency of the extraction process is studied. More efficient extraction was observed for the PDEAAm copolymers when compared with the PNIPAAm copolymers and conventional surfactants. In the study of the Sonogashira coupling reactions in water, aggregative precipitation of the products was observed. Washing the precipitate with water gave the product with satisfactory purity with a good yield.

Calcium-phosphate cements (CPCs) have been used as bone filling materials in orthopaedic surgery. However, CPCs are set using an acid-base reaction, and then change into stable hydroxyapatite (HAp) in a living body. Therefore, we developed bioresorbable chelate-setting β-tricalcium phosphate (β-TCP) cements based on surface modifications of inositol phosphate (IP6). In order to improve the bioresorbability, we fabricated IP6/β-TCP cements hybridized with poly(lactic-co-glycolic acid) (PLGA) particles as a pore-forming agent. The compressive strengths of the cements with the amounts of 5 and 10 mass% PLGA particles were 23.2 and 22.8 MPa, respectively. There was no significant difference from cements without PLGA (23.4 MPa). The setting times of the cement specimens with PLGA particles (30 min) were a little longer than those without PLGA particles (26.3 min). The lack of cytotoxicity of the cement specimens was confirmed using osteoblast-like cells (MC3T3-E1). Cylindrical defects were made by drilling into the tibia of mini-pigs and injecting the prepared cement pastes into the defects. Twelve weeks after implantation the specimens were stained with toluidine blue and histologically evaluated. Histological evaluation of cement specimens with PLGA particles showed enhanced bioresorbability. Newly-formed bone was also observed inside cement specimens with PLGA particles. The IP6/β-TCP cement specimens with PLGA particles had excellent material properties, such as injectability, compressive strength, high porosity, no cytotoxicity in vitro, bioresorption and bone formation abilities in vivo. Organic-inorganic hybridized CPCs are expected to be valuable as novel biodegradable paste-like artificial bone fillers.

Solid polymer electrolytes mainly based on polyethers have been actively investigated for over 40 years to develop safe, light, and flexible rechargeable batteries. Here, we report novel supramolecular electrolytes (SMEs) composed of polyether derivatives and a two-dimensional boroxine skeleton synthesized by the dehydration condensation of 1,4-benzenediboronic acid in the presence of a polyether with amines on both chain ends. The formation of SMEs based on polyether derivatives and boroxine skeleton was confirmed by Fourier transform infrared (FT-IR) spectroscopy, X-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (PXRD), and thermogravimetric (TG) analysis. Linear sweep voltammetry (LSV) and cyclic voltammetry (CV) were performed to evaluate the electrochemical stability and lithium conductive properties of SMEs with given amounts of lithium bis(trifluoromethylsulfonyl)amide (LiTFSA). The ionic conductivity of SME/LiTFSA composites increased with increasing lithium-salt concentration and reached a maximum value at a higher concentration than those of simple polyether systems. The lithium-ion transference number (t(Li+)) of SME/LiTFSA was higher than those of polyether electrolytes. This tendency is unusual for a polyether matrix. SME/LiTFSA composite electrolytes exhibited a stable lithium plating/striping process even after 100 cycles. The current density increased with an increasing number of cycles. The combination of ion conductive polymers and a two-dimensional boroxine skeleton will be an interesting concept for developing solid electrolytes with good electrochemical properties.

A 2D perovskite incorporating an amine moiety with a carboxy group exhibited orientation changes as the amount of DMSO additive varied. The degree of perpendicular orientation was increased by optimizing the amount of DMSO additive, while using the bar-coating method. Moreover, film thickness and the ratio of perpendicular orientation exhibited a positive correlation.

Poly (ethylene oxide) (PEO) has been investigated as an ion-conductive matrix for several decades due to its excellent properties. However, further improvements are needed to enable a PEO-based ion-conductive matrix for practical applications. In order to develop novel solid polymer electrolytes based on zwitterions, we synthesized diblock copolymers (PPEGMA-b-SPBs) with oligoether and zwitterionic side-chains and evaluated their physico-chemical properties. PPEGMA-b-SPBs with various unit ratios were synthesized by RAFT polymerization. PPEGMA-b-SPBs with/without LiTFSA exhibited two distinct glass transition temperatures regardless of the unit ratio of PEGMA and SPB. AFM observations clearly revealed phase-separated structures. The ionic conductivity of PPEGMA-b-SPBs increased even at a high salt concentrations such as [EO]:[Li] = 6:1 and was over 10(-5) S cm(-1) at 25 degrees C. This tendency is unusual in a PEO matrix. The oxidation stability of PPEGMA-b-SPBs was about 5.0 V vs. Li/Li+, which is a higher value than that of PEO. The improvement of the electrochemical properties is attributed to the introduction of the SPB block into the block copolymers. PPEGMA-b-SPBs were evaluated as cathode-coating materials for Li batteries. The discharge capacity and coulombic efficiency of the cells employing the cathode (LiNi1/3Mn1/3Co1/3O2 (NMC)) coated with the block copolymers were much higher than those of the cell employing the pristine cathode at the 50th cycle in the cut-off voltage range of 3.0-4.6 V.

Cellulose is the main component of biomass and is the most abundant biopolymer on earth; it is a non-toxic, low-cost material that is biocompatible and biodegradable. Cellulose gels are receiving increasing attention as medical products, e.g., as wound dressings. However, the preparation of cellulose hydrogels employing unmodified cellulose is scarcely reported because of the cumbersome dissolution of cellulose. In previous studies, we developed the new promising cellulose solvent N-butyl-N-methylpyrrolidinium hydroxide in an aqueous solution, which can dissolve up to 20 wt% cellulose within a short time at room temperature. In this study, we employed this solvent system and investigated the gelation behavior of cellulose after crosslinker addition. The swelling behavior in water (swelling ratio, water uptake), the mechanical properties under compression, and the antibacterial activity against Escherichia coli and Bacillus subtilis were investigated. We have developed a simple and fast one-pot method for the preparation of cellulose gels, in which aqueous pyrrolidinium hydroxide solution was acting as the solvent and as an antibacterial reagent. The pyrrolidinium hydroxide content of the gels was controlled by adjustment of the water volume employed for swelling. Simple recovery of the solvent system was also possible, which makes this preparation method environmentally benign.

Organic ionic plastic crystals (OIPCs) have been studied as solid-state electrolytes owing to their desirable properties such as plasticity, non-flammability, and high ionic conductivity. However, the relationship between the ion structures and the properties of OIPCs are poorly understood. To supplement our previous work on the effects of the side chain structure of pyrrolidinium salts on their properties, this study examined the effects of the anion structure. For this purpose, five N,N-diethylpyrrolidinium ([C(2)epyr]) salts with various sulfonylamide anions were synthesized. The [C(2)epyr] salts with bis(fluorosulfonyl)amide ([FSA]) and bis(pentafluoroethanesulfonyl)amide ([BETA]) exhibited higher ionic conductivity values at room temperature than the other [C(2)epyr] salts. The H-1 and F-19 solid-state NMR results indicated that the component ions in [C(2)epyr][FSA] and [C(2)epyr][BETA] exhibited high rotational mobility, even in the solid state. Thus, rotational mobility is likely important for achieving high ionic conductivity.

Acetone, regarded as a poor solvent for perovskite materials, was found to be suitable for synthesis of the perfluoroalkyl-based two-dimensional (2D) perovskite (C3F7CH2NH3)(2)PbBr4. One-step synthesis gave this material as a pure phase exhibiting quantum- and dielectric-confinement effects. However,N,N-dimethylformamide (DMF), a traditional perovskite solvent, did not produce these properties.

The power conversion efficiency (PCE) of organic solar cells (OSCs) has been gradually increasing over the past years, but these emerging photovoltaic devices still suffer from relatively short lifetimes. To promote circular economy and reduce costly electronic materials wastes, we explore the possibility of recycling durable zinc oxide coated indium tin oxide (ITO/ZnO) from nonfullerene OSCs through sequential ultrasonication in a series of solvents followed by thermal annealing. With the adequate cleaning sequence, the recycled ITO/ZnO substrates produce PCEs of 8.65%, a value comparable to the PCEs obtained with freshly prepared substrates (8.73%). Our results also indicate that isopropanol gradually removes the zinc oxide layer and should thus be avoided when attempting multiple successive recycling of the same substrate. ITO/ZnO substrates recycled 10 times with and without isopropanol yield PCEs of 5.14% and 7.93%, respectively. By optimizing the recycling procedure, we introduce a simple strategy to considerably increase the lifecycle of transparent electrode substrates employed in organic electronic devices and decrease the amount of wastes from the electronic industry.

Conjugated polyelectrolytes are commonly employed as interlayers to modify organic solar cell (OSC) electrode work functions but their use as an electron donor in water-processed OSC active layers has barely been investigated. Here, we demonstrate that poly[3-(6'-N,N,N-trimethyl ammonium)-hexylthiophene] bromide (P3HTN) can be employed as an electron donor combined with a water-soluble fullerene (PEG-C-60) into eco-friendly active layers deposited from aqueous solutions. Spin-coating a poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) layer prior to the P3HTN:PEG-C-60 active layer deposition considerably increases the open-circuit voltage (V-oc) of the OSCs to values above 1.3 V. Along with this enhanced V-oc, the OSCs fabricated with the PEDOT:PSS interlayers exhibit 10-fold and 5-fold increases in short-circuit current density (J(sc)) with respect to those employing bare indium tin oxide (ITO) and molybdenum trioxide coated ITO anodes, respectively. These findings suggest that the enhanced J(sc) and V-oc in the water-processed OSCs using the PEDOT:PSS interlayer cannot be solely ascribed to a better hole collection but rather to ion exchanges taking place between PEDOT:PSS and P3HTN. We investigate the optoelectronic properties of the newly formed polyelectrolytes using absorption and photoelectron spectroscopy combined with hole transport measurements to elucidate the enhanced photovoltaic parameters obtained in the OSCs prepared with PEDOT:PSS and P3HTN.

Cellulose processing remains a challenge as it is insoluble in water and common organic solvents. Ionic liquids (ILs) are organic salts with a melting point below 100 degrees C and are known for their excellent solvent properties. Unlike common organic solvents, which can form toxic or flammable vapours due to their high volatility, ILs can be considered as more environmentally friendly due to their negligible vapour pressure and flame retardant properties. We found that N-butyl-N-methylpyrrolidinium hydroxide enables rapid dissolution of up to 20 wt% Avicel (R) cellulose at 25 degrees C in aqueous solution (50 wt% water), making it the first pyrrolidinium-based salt capable of dissolving cellulose. Furthermore, solubility studies are currently carried out mainly with the naked eye, microscopy or spectroscopy. The former is a subjective method because it depends on the observer, and particles at the micro-level cannot be seen with the human eye. Microscopic and spectroscopic analyses are suitable for the verification of solubility; however, the acquisition costs of the instruments are high, and sample preparation is time-consuming. We propose that turbidity is a suitable measure for solubility, and investigated a simple and fast method to evaluate cellulose solubility in aqueous N-butyl-N-methylpyrrolidinium hydroxide by employing a turbidimeter which was compared with microscopy and ocular (eye) observation. In this study, we have not only found a promising new solvent for cellulose processing, but also offer a reliable solubility analysis.

To achieve precise control of sulfonated polymer structures, a series of poly(p-phenylene)-based ionomers with well-controlled ion exchange capacities (IECs) were synthesised via a three-step technique: (1) preceding sulfonation of the monomer with a protecting group, (2) nickel(0) catalysed coupling polymerisation, and (3) cleavage of the protecting group of the polymers. 2,2-Dimethylpropyl-4-[4-(2,5-dichlorobenzoyl)phenoxy]benzenesulfonate (NS-DPBP) was synthesised as the preceding sulfonated monomer by treatment with chlorosulfuric acid and neopentyl alcohol. NS-DPBP was readily soluble in various organic solvents and stable during the nickel(0) catalysed coupling reaction. Sulfonated poly(4-phenoxybenzoyl-1,4-phenylene) (S-PPBP) homopolymer and seven types of random copolymers (S-PPBP-co-PPBP) with different IECs were obtained by varying the stoichiometry of NS-DPBP. The IECs and weight average molecular weights (M(w)s) of ionomers were in the range of 0.41-2.84 meq. g(-1) and 143 000-465 000 g mol(-1), respectively. The water uptake, proton conductivities, and water diffusion properties of ionomers exhibited a strong IEC dependence. Upon increasing the IEC of S-PPBP-co-PPBPs from 0.86 to 2.40 meq. g(-1), the conductivities increased from 6.9 x 10(-6) S cm(-1) to 1.8 x 10(-1) S cm(-1) at 90% RH. S-PPBP and S-PPBP-co-PPBP (4 : 1) with IEC values >2.40 meq. g(-1) exhibited fast water diffusion (1.6 x 10(-11) to 8.0 x 10(-10) m(2) s(-1)), and were comparable to commercial perfluorosulfuric acid polymers. When fully hydrated, the maximum power density and the limiting current density of membrane electrode assemblies (MEAs) prepared with S-PPBP-co-PPBP (4 : 1) were 712 mW cm(-2) and 1840 mA cm(-2), respectively.

Organic-inorganic perovskites are composed of organic cations and [PbX6](4-) octahedra, and the properties change depending on the type of organic cations. To identify the effect of organic cations and control the properties of the perovskite, thin films were prepared using quaternary alkylammonium and quaternary alkylphosphonium cations, which have big steric effects. A big steric effect can generate the distortion of [PbX6](4-) octahedra leading to changes in properties. A thin film of a Pb-based organic-inorganic perovskite having quaternary alkylphosphonium cations was prepared for the first time. An exciton absorption was observed at a lower wavelength than other perovskites prepared from primary and quaternary ammonium salts. The perovskite with phosphonium groups was thermally stable compared with ammonium groups.

A two-dimensional perovskite incorporating an amine moiety with a carboxyl group exhibited variations in orientation with changes in the ambient humidity. It was possible to increase the degree of vertical orientation by optimizing the film thickness and promoting crystallization at the interface between the film and the film-forming atmosphere.

Organic ionic plastic crystals (OIPCs) have been studied as solid-state electrolytes because of their desirable properties such as non-flammability, plasticity, and ionic conductivity. However, the temperature range of their conductive plastic crystal phase is narrow. We previously reported that N-ethyl-N-methylpyrrolidinium bis(fluorosulfonyl) amide ([C(2)mpyr][FSA]) exhibited a wide temperature range of plastic crystal behavior and high ionic conductivity at room temperature. In this study, the relationship between the side chain structure of pyrrolidinium and the physicochemical properties of their compounds with FSA was investigated. With two introduced ethyl groups, N, N-diethylpyrrolidinium bis(fluorosulfonyl) amide ([C(2)epyr][FSA]) showed higher ionic conductivity than [C(2)mpyr][FSA], while maintaining a sufficient temperature range of plastic crystal phase. The ionic conductivity of [C2epyr] [FSA] was further improved by the addition of 5 mol% LiFSA. For the [C(2)epyr][FSA] composited with 5 mol % LiFSA, the lithium transference number was determined to be 0.27 at 60 degrees C. Reversible lithium plating/ stripping reaction was observed on a Ni electrode in the CV measurement. Symmetric pyrrolidinium cation with a longer alkyl chain (up to two carbons) showed conductive plastic solid phase in a wide temperature range and a higher lithium transference number. (c) 2019 Elsevier Ltd. All rights reserved.

Push-coating is a simple process that can be employed for extremely low-cost polymer electronic device production. Here, we demonstrate its application to the fabrication of poly(2,7-carbazole-alt-dithienylbenzothiadiazole) (PCDTBT):[6,6]-phenyl-C-71-butyric acid methyl ester (PC71BM) active layers processed in air, yielding similar photovoltaic performances as thermally annealed spin-coated thin films when used in inverted polymer solar cells (PSCs). During push-coating, the polydimethylsiloxane layer temporarily traps the deposition solvent, resulting in simultaneous film formation and solvent annealing effect. This removes the necessity for a postdeposition thermal annealing step which is required for spin-coated PSCs to produce high photovoltaic performances. Optimized PSC active layers are produced with a push-coating time of 5 min at room temperature with 20 times less hazardous solvent and 40 times less active material than spin-coating. Annealed spin-coated active layers and active layers push-coated for 5 min both produce average power conversion efficiencies (PCEs) of 5.77%, while those push-coated for a shorter time of 1 min yield a slightly lower value of 5.59%. We demonstrate that, despite differences in their donor:acceptor vertical concentration gradients, unencapsulated PCDTBT:PC71BM active layers push-coated for 1 min produce PSCs with similar operational stability and upscaling capacity as thermally annealed spin-coated ones. As fast device fabrication can be achieved with short-time push-coating, we further demonstrate the potential of this deposition technique by manufacturing push-coated PSC-based semitransparent photovoltaic devices with a PCE of 4.23%, relatively neutral colors and an average visible transparency of 40.2%. Our work thus confirms that push-coating is not limited to the widely employed poly(3-hexylthiophene-2,5-diyl) but can also be used with low band gap copolymers and opens the path to low-cost and eco-friendly, yet efficient and stable PSCs.

Ionic liquids (Ls) are promising electrolyte materials for developing next-generation rechargeable batteries. In order to improve their properties, several kinds of additives have been investigated. In this study, beta-cyclodextrin (beta-CD) was chosen as a new additive in IL electrolytes because it can form an inclusion complex with bis(trifluoromethylsulfonyl)amide (TFSA) anions. We prepared the composites by mixing N-methyl-N-propylpyrrolidinium bis(trifluoromethylsulfony)amide/LiTFSA and a given amount of triacetyl-beta-cyclodextrin (Ac beta-CD). The thermal behaviors and electrochemical properties of the composites were analyzed by several techniques. In addition, pulse field gradient NMR measurements were conducted to determine the self- diffusion coefficients of the component ions. The addition of Ac beta-CD to the IL electrolytes results in the decrease in the conductivity value and the increase in the viscosity value. In contrast, the addition of Ac beta-CD to the IL electrolytes induced an improvement in the anodic stability because of the formation of an inclusion complex between the Ac beta-CD and TFSA anions. CDs are potential candidates as additives in IL electrolytes for electrochemical applications.

Five kinds of protic ionic liquids (PILs) were synthesized by the neutralization reaction of amidine and carboxylic acid (acetic acid, propionic acid, or butyric acid), and the esterification reaction of cellulose, using acetic anhydride, was carried out in PILs. The obtained cellulose derivatives were soluble in DMSO. In the H-1 NMR spectra of the cellulose derivatives, not only the chemical shift of acetyl group derived from acetic anhydride, but also the chemical shift, based on the anion of PILs, were observed. The degree of substitution (DS) of the produced cellulose derivatives varied depending on the structure of PILs. The obtained cellulose derivatives showed a thermal decomposition temperature above 270 degrees C and a glass transition temperature below 170 degrees C.

A protic ionic liquid (PIL) composed of 1,8-diazabicyclo[5.4.0]-undec-7-ene (DBU) and acetic acid can dissolve cellulose under mild conditions and catalyse its transesterification. To investigate the relationship between physicochemical properties and chemical structures, PILs composed of DBU and carboxylic acids with varying alkyl chain lengths were prepared as cellulose-dissolving solvents. The thermal behaviours of the PILs were analysed by thermogravimetry and differential scanning calorimetry, and their viscosities, ionic conductivities, and cellulose-dissolution abilities were determined. The effect of the alkyl chain length in the carboxylate ion on the physicochemical properties of the PILs was investigated. With increasing chain length, the thermal stability and ionic conductivity increased, whereas the melting point (T-m), glass-transition temperature (T-g), cellulose solubility, and viscosity decreased. The cellulose solubility increased as the difference between the pK(a) values of the DBU and carboxylic acid (Delta pK(a)) increased. In addition, the cellulose solubility increased with the increasing density of the PIL. It was revealed that PILs with a high DpKa value and a carboxylate ion with a short alkyl chain are suitable for cellulose dissolution.

Organic-inorganic perovskites, (RNH3)(2)PbX4, have attracted much attention as one of the most promising light-harvesting and light-emitting materials. The present work investigated the steric effects of the organic parts on the perovskites by varying the alkylamine type and chain length. Primary, secondary, and tertiary amines with various chain lengths were introduced into organic-inorganic perovskites. Extending the chain length raised the phase transition point and shortened the absorption wavelength. In addition, the introduction of secondary and tertiary amines resulted in red-and blue-shifting of the absorption peaks, respectively.

This study demonstrates the supramolecular chirality control of a conjugated polymer via solvent polarity. We designed and synthesized a chiral polyfluorene-thiophene copolymer having two different chiral side chains at the 9-position of the fluorene unit. Chiral cyclic and alkyl ethers with different polarities were selected as the chiral side chains. The sign of the circular dichroism spectra in the visible wavelength region was affected by the solvent system, resulting from the change of supramolecular structure. The estimation of the solubility parameter revealed that the solubility difference of the side chains contributed to the change of the circular dichroism sign, which was also observed in spin-coated films prepared from good solvents having different polarities.

Cellulose acetate (CA) is a resin derived from biomass. In addition to its various superior properties, CA is preferable to existing petroleum-derived resins from the viewpoint of green chemistry. Therefore, the acetylation of cellulose is one of the most important subjects in cellulose research. In this study, we found that the acetylation of cellulose could proceed in some protic ionic liquids (PILs) composed of amidine and acetic acid with pK(a) = ca. 8.4-8.7 under mild conditions without any catalyst. The degree of substitution (DS) of the produced CA was above 1.84, and the maximum DS was 2.87 when the pK(a) of the PIL was about 8.5. In propionate-based PILs, cellulose was not only acetylated but also propionated; however, the cellulose acetylation did not occur in formate-based PILs. It was revealed that the esterification of cellulose proceeded through the anion exchange between carboxylic anhydride and anion species of the PIL.

Ionic liquids (ILs) containing zwitterions were studied as electrolytes for lithium-ion batteries. The effect of a pyrrolidinium zwitterion with a long ether side chain on the thermal and electrochemical properties of an IL and the charge/discharge properties of Li/LiCoO2, Li/LiNi1/3Mn1/3Co1/3O2 (NMC), and graphite/Li cells with IL/zwitterion electrolytes was investigated. The melting temperature of the IL-based electrolyte composed of N-methyl-N-methoxymethylpyrrolidinium bis(fluorosulfonyl) amide ([Pyr(1,101)] [FSA]) and lithium bis(fluorosulfonyl) amide (LiFSA) with 3-(1-(2-(2-methoxyethoxy)ethyl)pyrrolidin-1-ium-1-yl)propane-1-sulfonate (OE2pyps) as the zwitterionic additive was about -18 degrees C. The electrochemical window of [Pyr(1,101)][FSA]/LiFSA/OE2pyps was over 5 V vs. Li/Li+. Li|electrolyte| LiCoO2 cells containing the [Pyr(1,101)][FSA]/LiFSA/OE2pyps electrolyte system exhibited high capacity values in the cut-off voltage range of 3.0-4.3 V, even after 50 cycles. Moreover, increases of interfacial resistance between the electrolyte and cathode during cycling were suppressed. Li|electrolyte|NMC cells containing this electrolyte system also exhibited high capacities in a wide cut-off voltage range of 3.0-4.6 V, even after 50 cycles. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions was observed between 0 and + 0.4 V vs. Li/Li+. Further, graphite|electrolyte|Li cells containing [Pyr(1,101)][FSA]/LiFSA/OE2pyps exhibited stable charge/discharge cycle behavior over 5 cycles. (C) 2017 Elsevier Ltd. All rights reserved.

Two-dimensional perovskite compounds, ((RNH32PbX4)-Pb-), have attracted much attention as quantum confinement materials. To achieve suitable orientation and exciton properties for optical applications, carboxy groups were introduced into the ammonium cations of two-dimensional perovskite compounds, which formed dimer structures based on the hydrogen bonding by the carboxy moieties. This structural organization allowed control of the layer orientation for favorable solar cells and thermal stability of the perovskites, while maintaining quantum confinement effects.

We demonstrate efficiency enhancement in perovskite solar cells (PSCs) utilizing a free-dopant hole transporting material (HTM), non-peripherally substituted octapentyl phthalocyanine (C5PcH(2)) with thermal annealing. Particularly, by using thermal annealing approach, the external quantum efficiency at around 480 nm increase from 78 to 84%. Hence, the fill factor and short-circuit current density are markedly improved from 0.35 +/- 0.02 to 0.55 +/- 0.05 and from 18 +/- 1 to 18.8 +/- 0.3 mA cm(-2), respectively. Finally, the best device is achieved with power conversion efficiencies of 12.2% by annealing at 130 degrees C for 10 min. The photoluminescence and photo-induced charge carrier extraction in linearly increasing voltages measurements indicate that the charge carrier mobility in C5PcH(2) increases, and thereby the hole extraction and transportation from the perovskite layer to the Au anode as well the photovoltaic performance of PCS is improved by using thermal annealing processing. (C) 2017 Elsevier B.V. All rights reserved.

Formamidine (FA) and cesium (Cs) cations were introduced into quasi-two-dimensional (2D) perovskites as B site cations. The unique crystalline growth of the resulting (n-C6H13NH3)(2)FAPb(2)I(7), which promotes charge transport in photovoltaic solar cells, was confirmed, as was the stability of this material. The photovoltaic properties of (n-C6H13NH3)(2)FAPb(2)I(7) were found to be superior to those of other homologous quasi-2D perovskite compounds.

Colorless and transparent polybetaine-type ion gels (PEG(100)CL(2)BT(x) (x = 0, 1, 3, 5, and 10) (the numbers indicate mole percent)) composed of poly(ethylene glycol) methyl ether methacrylate (PEGMA), [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl) ammonium hydroxide (BT) as the polymer matrix, N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)amide/lithium bis(trifluoromethylsulfonyl)amide (IL/Li) as the electrolyte, and a cross-linker (CL) were synthesized by in situ polymerization. These ion gels exhibited a glass transition temperature (T-g) at approximately -70 degrees C, and their ionic conductivity was almost the same regardless of the x value. On the other hand, the oxidation stability of ion gels increased with increasing BT content. All ion gels exhibited a reduction peak for Li+ and an oxidation peak for Li. The current density and coulombic efficiency of PEG(100)CL(2)BT(5) were higher than those of PEG(100)CL(2)BT(0).

Ionic liquids (ILs) containing zwitterions have been studied as electrolytes for lithium-ion batteries (LIBs). The effects of addition of a pyrrolidinium zwitterion in an IL electrolyte on the thermal and electrochemical stability and charge/discharge properties of Li/LiCoO2 and graphite/Li cells were investigated. The thermal decomposition temperature of the IL electrolyte composed of N-methyl-N-propylpyrrolidinium bis(fluorosulfonyl)amide ([P13][FSA])/lithium bis(trifluoromethylsulfonyl)amide (LiTFSA) with 3-(1-butylpyrrolidinium)propane-1-sulfonate (Bpyps) as the zwitterionic additive, the thermal decomposition temperature was about 300 degrees C. The electrochemical window of [P13][FSA]/LiTFSA/Bpyps was 0 -+5.4 V vs. Li/Li+, which was almost identical to that of [P13][FSA]/LiTFSA. Li vertical bar electrolyte vertical bar LiCoO2 cells containing the IL/Bpyps electrolyte system exhibited high capacities in the cut-off voltage range of 3.0 -4.6 V, even after 50 cycles. The increase in the interfacial resistance between the electrolyte and cathode with cycling was suppressed. In the cyclic voltammograms of cells employing a graphite electrode, the intercalation/deintercalation of lithium ions were observed in the range of 0 and + 0.4 V vs. Li/Li+. Further, graphite vertical bar electrolyte vertical bar Li cells containing [P13][FSA]/LiTFSA/Bpyps exhibited stable charge/discharge cycle behaviour over 50 cycles. (C) 2016 Elsevier B.V. All rights reserved.

Aromatic ionomers with perfluoroalkyl sulfonic acid groups for fuel cell applications have been prepared mostly by the post-functionalization method. Herein, we present a direct polymerization method using a novel monomer with a perfluorosulfonic acid group to control the amount and position of the sulfonic acid groups. A poly(p-phenylene)- based aromatic hydrocarbon ionomer bearing a pendant perfluorosulfonic acid group in a substituent at the 2-position is synthesized by Ni(0)-catalyzed coupling polymerization. The direct polymerization provides M-n values of up to 169 000 with a highly controlled molecular structure and allows the formation of thin membranes. These ionomers were found to combine the positive features of perfluorinated and aromatic hydrocarbon ionomers, and these thin membranes with a relatively high ion exchange capacity showed high proton conductivity and excellent fuel cell performance (907 mW cm(-2) even at 80 degrees C and 30% RH) under low humidity conditions compared with other reported aromatic hydrocarbon ionomers.

The ionic liquid (IL) N-Methyl-N-methoxymethylpyrrolidinium bis(fluorosulfonyl)amide ([Pyr(1,101)][FSA]) was synthesized, and its physicochemical and electrochemical properties were investigated with respect to its application as an electrolyte in lithium-ion secondary batteries operating over a wide temperature range. [Pyr(1,101)][FSA]/Li salt (0.34 mol kg) composites were prepared by adding lithium bis(tri-fluoromethylsulfonyl)amide (LiTFSA) into the IL. [Pyr(1,101)][FSA] and [Pyr(1,101)][FSA]/LiTFSA exhibited melting temperatures (T-m) below 30 degrees C. [Pyr(1,101)][FSA] exhibited a higher ionic conductivity value as compared with that of the corresponding IL with only alkyl substituents. The electrochemical window for both [Pyr(1,101)][FSA] and [Pyr(1,101)][FSA]/LiTFSA was 5.1 V. Stable lithium deposition and dissolution occurred on a Ni electrode at 25 degrees C. (C) 2016 Elsevier B.V. All rights reserved.