Kyoto University · 재료과학
Yukihiro Yoshida 교수의 연구실은 주로 이온성 액체의 설계 및 응용에 초점을 맞추고 있으며, 특히 다양한 카이드로겐 결합, 금속 리간드 복합체, 그리고 다공성 고체(예: MOFs)에 이온성 액체를 통합하는 연구를 진행하고 있습니다. 고온에서의 높은 이온 전도도와 낮은 점도를 갖는 기능성 이온성 액체의 개발, 그리고 이들의 전기화학적 성질과 상전이 행동을 체계적으로 분석함으로써 고성능 전해질 소재를 설계하는 데 목적이 있습니다. 특히 초전도체 수준의 이온 전도성을 나타내는 IL@MOF 복합체의 개발은 차세대 전지 및 전기화학 장치의 핵심 소재로 주목받고 있습니다.
표시된 성과는 수집된 데이터 기준으로 산출되며, 일부 차이가 있을 수 있습니다.
New 1-ethyl-3-methylimidazolium (EMI) salts [EMI][C(CN)3] and [EMI][Ag(CN)2] were prepared and characterized. The C(CN)3 salt has a melting point at -11 degrees C and shows a low viscosity (18 cP) and a high ionic conductivity (1.8 x 10(-2) S cm(-1)) at room temperature. This conductivity is less than that of [EMI][N(CN)2] salt (2.7 x 10(-2) S cm(-1)), possibly due to the larger molecular weight of the anion. The first EMI salt containing Ag(I) complexes [EMI][Ag(CN)2] has a higher melting point
A series of dicyanamide [N(CN)2]-based ionic liquids were prepared using 1-alkyl-3-methylimidazolium cations with different alkyl chain lengths and ethyl-containing heterocyclic cations with different ring structures, and the influence of such structural variations on their thermal property, density, electrochemical window, viscosity, ionic conductivity, and solvatochromic effects was investigated. We found that the 1,3-dimethylimidazolium salt shows the highest ionic conductivity among ionic li
A series of paramagnetic ionic liquids, which are comprised of 1-alkyl-3-methylimidazolium RMI+ cation (R = Et, n-Bu, n-hexyl and n-octyl) and tetrahalogenoferrate(III) FeX4− anion (X = Cl and Br), were prepared, and the influence of structural variations such as changing the alkyl chain (R) length in the cation and substituting the halides (X) in the anion on their thermal behavior, infrared and ultraviolet-visible absorption spectra, density, viscosity, ionic conductivity and magnetic suscepti
Encapsulation of ionic liquids (ILs) into porous materials can provide environmentally benign solid-state electrolytes for various electrochemical devices, in particular, porous metal–organic frameworks (MOFs) that enable us to tailor their framework and pore structures by varying central metals and organic linkers as well as the ILs with an unlimited number of possible cation–anion combinations. Therefore, rational materials design based on the accumulated knowledge about the relationship betwe
Some recent developments concerning the syntheses and physical properties of functional ionic liquids, especially those having paramagnetic and luminescent properties, are highlighted. The component ions used so far include both inorganic and organic types; and various strategies, namely not only the proper choice but also the synthesis of anions to impart the functionality, are presented.
Most molecules in confined spaces show markedly different behaviors from those in the bulk. Large pores are composed of two regions: an interface region in which liquids interact with the pore surface, and a core region in which liquids behave as bulk. The realization of a highly mobile ionic liquid (IL) in a mesoporous metal-organic framework (MOF) is now reported. The hybrid shows a high room-temperature conductivity (4.4×10<sup>-3</sup> S cm<sup>-1</sup> ) and low activation energy (0.20 eV);
Abstract An EMI-based room-temperature (RT) ionic liquid containing d5 trivalent iron(III) ions [EMI][FeIIICl4] was fully investigated, where EMI is 1-ethyl-3-methylimidazolium. The viscosity of the salt is 14 cP at 30 °C, and its ionic conductivity is as high as 1.8 × 10−2 S cm−1 at 20 °C. The high conductivity and fluidity can be attributed to the reduced interionic Coulomb attractions owing to the nephelauxetic effect. Magnetic susceptibility shows the Curie–Weiss behavior arising from S = 5/
Article An object code compression approach to embedded processors Share on Authors: Yukihiro Yoshida Dept. Information Systems Engineering, Osaka University Dept. Information Systems Engineering, Osaka UniversityView Profile , Bao-Yu Song Dept. Information Systems Engineering, Osaka University Dept. Information Systems Engineering, Osaka UniversityView Profile , Hiroyuki Okuhata Dept. Information Systems Engineering, Osaka University Dept. Information Systems Engineering, Osaka UniversityView P
Ionic liquids composed of dicyanamide anion and various imidazolium-based cations were prepared, and the influence of structural variations such as substituting a hydrogen at 2-position and changing the sort of alkyl group at 1-position of imidazolium cations on their thermal behavior, density, solvatochromic effects, viscosity, ionic conductivity, and surface tension was characterized. The substitution of the 2-hydrogen for methyl group or N-methylimidazole decreases the fluidity and ionic cond
Abstract A series of genuine organic paramagnetic ionic liquids were prepared utilizing 2,2,6,6-tetramethyl-1-piperidinyloxyl-4-sulfate (TEMPO-OSO3) anion with S=1⁄2 radical spin. Their static susceptibilities and EPR spectra can be explained in terms of the paramagnetic spins on the TEMPO radical moieties, although they have much low fluidities and ionic conductivities.
The elastocaloric properties of poly (vinylidene fluoride-trifluoroethylene-chlorotrifluoroethylene) [P(VDF-TrFE-CTFE)] terpolymer were directly characterized using an infrared imaging camera. At a strain of 12%, a reversible adiabatic temperature variation of 2.15 °C was measured, corresponding to an isothermal entropy variation of 21.5 kJ m−3 K−1 or 11 J kg−1 K−1. In comparison with other elastocaloric materials, P(VDF-TrFE-CTFE) appears to represent a trade-off between the large required stre
36 kinds of donor(D)–acceptor(A) type charge transfer (CT) solids were prepared based on ethylenedioxyethylenedithiotetrathiafulvalene (EDOEDT-TTF or EOET), which is a hybrid molecule of bis(ethylenedioxy)-TTF (BEDO-TTF or BO) and bis(ethylenedithio)-TTF (BEDT-TTF or ET). A plot of the first CT absorption bands in solids against the difference in first redox potential between donor and acceptor molecules (ΔE) classified the complexes into five groups, A: highly conductive CT complexes with parti
A series of diethylmethyl(2-methoxyethyl)ammonium (DEME)-based ionic liquids were prepared using bis(perfluoroalkanesulfonyl)amide (C(n)F(2n+1)SO(2))(2)N anions with different perfluoroalkyl chain lengths (n = 0, 1, 2, 3, and 4), and the influence of the structural variation on their thermal, ion-diffusive (ionic conductivity and viscosity), ion-concentration (molar concentration and ion association), and solvatochromic (polarity and hydrogen-bond acceptor ability) properties was investigated. T