Physicochemical properties and structures of room-temperature ionic liquids. 3. Variation of cationic structures
| Autor: | Kikuko Hayamizu, Masayoshi Watanabe, Hiroyuki Tokuda, Kunikazu Ishii, Seiji Tsuzuki, Md. Abu Bin Hasan Susan |
|---|---|
| Rok vydání: | 2006 |
| Předmět: |
Diffusion
Inorganic chemistry Cationic polymerization Analytical chemistry Molar conductivity Atmospheric temperature range Surfaces Coatings and Films Ion chemistry.chemical_compound Viscosity chemistry Ionic liquid Physics::Atomic and Molecular Clusters Materials Chemistry Ionic conductivity Physics::Chemical Physics Physical and Theoretical Chemistry |
| Zdroj: | The journal of physical chemistry. B. 110(6) |
| ISSN: | 1520-6106 |
| Popis: | A series of room-temperature ionic liquids (RTILs) were prepared with different cationic structures, 1-butyl-3-methylimidazolium ([bmim]), 1-butylpyridinium ([bpy]), N-butyl-N-methylpyrrolidinium, ([bmpro]), and N-butyl-N,N,N-trimethylammonium ([(n-C(4)H(9))(CH(3))(3)N]) combined with an anion, bis(trifluoromethane sulfonyl)imide ([(CF(3)SO(2))(2)N]), and the thermal property, density, self-diffusion coefficients of the cation and anion, viscosity, and ionic conductivity were measured over a wide temperature range. The self-diffusion coefficient, viscosity, ionic conductivity, and molar conductivity follow the Vogel-Fulcher-Tamman equation for temperature dependencies, and the best-fit parameters have been estimated, together with the linear fitting parameters for the density. The relative cationic and anionic self-diffusion coefficients for the RTILs, independently determined by the pulsed-field-gradient spin-echo NMR method, appear to be influenced by the shape of the cationic structure. A definite order of the summation of the cationic and anionic diffusion coefficients for the RTILs: [bmim][(CF(3)SO(2))(2)N][bpy][(CF(3)SO(2))(2)N][bmpro][(CF(3)SO(2))(2)N][(n-C(4)H(9))(CH(3))(3)N][(CF(3)SO(2))(2)N], has been observed, which coincides with the reverse order to the viscosity data. The ratio of molar conductivity obtained from the impedance measurements to that calculated by the ionic diffusivity using the Nernst-Einstein equation quantifies the active ions contributing to ionic conduction in the diffusion components and follows the order: [bmpro][(CF(3)SO(2))(2)N][(n-C(4)H(9))(CH(3))(3)N][(CF(3)SO(2))(2)N][bpy][(CF(3)SO(2))(2)N][bmim][(CF(3)SO(2))(2)N] at 30 degrees C. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|