TY - JOUR
T1 - Mass transport properties in quasi-solidified lithium-ion conducting ionic liquids at oxide particle surfaces
AU - Unemoto, Atsushi
AU - Iwai, Yoshiki
AU - Mitani, Satoshi
AU - Baek, Seung Wook
AU - Ito, Seitaro
AU - Tomai, Takaaki
AU - Kawamura, Junichi
AU - Honma, Itaru
N1 - Funding Information:
This work was financially supported by the MIKIYA Science and Technology Foundation , the Funding Program for World-Leading Innovative R&D on Science and Technology (FIRST), “Innovative Basic Research Toward Creation of High-Performance Battery ”, and the Grant-in-Aid for Young Scientist (B) from the Japan Society for the Promotion of Science .
PY - 2012/10/4
Y1 - 2012/10/4
N2 - Lithium-ion conducting RTIL-Li-salt mixtures, 1MLi-TFSA/EMI-TFSA and 1MLi-FSA/EMI-FSA, were quasi-solidified at fumed SiO 2 particle surfaces. The electrical conductivities and the self-diffusion coefficients of the constituent species of the RTIL-Li-salt bulks and the composite materials, x vol%1MLi-TFSA/EMI-TFSA-fumed SiO 2 and x vol%1MLi-FSA/EMI-FSA-fumed SiO 2 (x = 100, 75 and 50), were evaluated. We have successfully quasi-solidified RTIL-Li-salts at fumed SiO 2 surfaces even though most of the composites are consisting of RTIL-Li-salts such as x = 75-80. The quasi-solid-state composites had liquid-like high electrical conductivities, e.g. 3.2 × 10 - 4 to 4.4 × 10 - 3 S cm - 1 for 75 vol%1MLi-TFSA/EMI-TFSA-fumed SiO 2 and 6.4 × 10 - 4 to 5.4 × 10 - 3 S cm - 1 for 75 vol%1MLi-FSA/EMI-FSA-fumed SiO 2, in the temperature range of 283-348 K. The self-diffusion coefficients of all constituent species become small as volume ratio of RTIL-Li-salt mixtures decreased. The effect of fumed silica surface on the transport properties of the RTILs depended on the RTIL structures. By receiving the effect from fumed silica surfaces, the disassociation of the ion pair, [EMI +][TFSA -], progressed for 1MLi-TFSA/EMI-TFSA while the Li-containing species lost their diffusivities for 1MLi-FSA/EMI-FSA.
AB - Lithium-ion conducting RTIL-Li-salt mixtures, 1MLi-TFSA/EMI-TFSA and 1MLi-FSA/EMI-FSA, were quasi-solidified at fumed SiO 2 particle surfaces. The electrical conductivities and the self-diffusion coefficients of the constituent species of the RTIL-Li-salt bulks and the composite materials, x vol%1MLi-TFSA/EMI-TFSA-fumed SiO 2 and x vol%1MLi-FSA/EMI-FSA-fumed SiO 2 (x = 100, 75 and 50), were evaluated. We have successfully quasi-solidified RTIL-Li-salts at fumed SiO 2 surfaces even though most of the composites are consisting of RTIL-Li-salts such as x = 75-80. The quasi-solid-state composites had liquid-like high electrical conductivities, e.g. 3.2 × 10 - 4 to 4.4 × 10 - 3 S cm - 1 for 75 vol%1MLi-TFSA/EMI-TFSA-fumed SiO 2 and 6.4 × 10 - 4 to 5.4 × 10 - 3 S cm - 1 for 75 vol%1MLi-FSA/EMI-FSA-fumed SiO 2, in the temperature range of 283-348 K. The self-diffusion coefficients of all constituent species become small as volume ratio of RTIL-Li-salt mixtures decreased. The effect of fumed silica surface on the transport properties of the RTILs depended on the RTIL structures. By receiving the effect from fumed silica surfaces, the disassociation of the ion pair, [EMI +][TFSA -], progressed for 1MLi-TFSA/EMI-TFSA while the Li-containing species lost their diffusivities for 1MLi-FSA/EMI-FSA.
KW - Dynamics
KW - Interface
KW - Lithium-ion conductor
KW - Quasi-solidification
KW - Room temperature ionic liquid
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U2 - 10.1016/j.ssi.2012.01.020
DO - 10.1016/j.ssi.2012.01.020
M3 - Article
AN - SCOPUS:84867576392
SN - 0167-2738
VL - 225
SP - 416
EP - 419
JO - Solid State Ionics
JF - Solid State Ionics
ER -