A structural study of LiTFSI-tetraglyme mixtures: From diluted solutions to solvated ionic liquids
Journal article, 2015
We report on the nano-structure of solvated ionic liquids (SILs) formed by dissolving a Li-salt (LiTFSI) in the solvent tetraglyme. Using small angle X-ray scattering (SAXS), supported by Raman spectroscopy and computational modeling we follow how the nano-structure develops as Li-salt is added to the solvent. We find that, as the Li-salt concentration is increased a peak at Q 0.95 Å- 1 grows in intensity, signaling the presence of structural correlations typical of those found in traditional ionic liquids. The intensity of the peak reaches its maximum at the equimolar concentration, where each Li-ion can be solvated by one solvent molecule forming an effective cation complex. Combining the SAXS data with computer modeling we show that this peak can be assigned to charge alternation, also found in traditional ionic liquids. However, we also show that even at the equimolar concentration not all Li-ions are solvated by the solvent molecules, but a small fraction interacts directly with the anion (TFSI).
Ionic liquids
Solvents
Electrolytes
Tetraglyme
Simulation
TFSI
Glymes
Solar cells
X ray scattering
Nanostructures
Lithium-ion batteries
SAXS
Molecules
Ions
Raman
Electrolyte
Batteries
Solvated ionic liquids
Liquids
Lithium
Author
Luis Aguilera Medina
Chalmers, Applied Physics, Condensed Matter Physics
Shizhao Xiong
National University of Defense Technology
Johan Scheers
Chalmers, Applied Physics, Condensed Matter Physics
Aleksandar Matic
Chalmers, Applied Physics, Condensed Matter Physics
Journal of Molecular Liquids
0167-7322 (ISSN)
Vol. 210 Part B 238-242Subject Categories
Condensed Matter Physics
DOI
10.1016/j.molliq.2015.04.053