Cationic and anionic environments in LiTFSI-doped di-ureasils with application in solid-state electrochromic devices
Journal article, 2008

Fourier Transform mid-infrared and Raman spectroscopies were used to investigate the cation/polymer, cation/urea bridge, cation/anion and hydrogen bonding interactions in poly(oxyethylene) (POE)/siloxane di-ureasil networks prepared by the sol-gel route and doped with lithium bis(trifluoromethanesulfonyl)imide (LiTFSI). Materials with compositions 200 >= n >= 5 (where n expresses the molar ratio OCH2CH2/Li+) were studied. The Li+ ions coordinate to the urea carbonyl oxygen atoms over the whole range of salt concentration considered. Bonding to the ether oxygen atoms of the POE chains occurs at n <= 40, although a significant fraction of the POE chains remain non-coordinated. In these high salt content samples, the cations interact with the anions forming contact ion pairs. "Free" ions are probably the main charge carriers at the room temperature conductivity maximum of these ormolytes. (C) 2008 Elsevier B.V. All rights reserved.

POLY(ETHYLENE OXIDE)

sol-gel

COMPLEXES

RAMAN-SPECTRA

ORMOLYTES

LIQUID

FT-Raman spectroscopy

LITHIUM PERCHLORATE

INFRARED TEMPERATURE

OXIDATION

FT-IR

POLYMER ELECTROLYTE

LiTFSI

PHYSICAL-PROPERTIES

di-ureasils

Author

S. C. Nunes

Universidade de Tras-os-Montes e Alto Douro

V. D. Bermudez

Universidade de Tras-os-Montes e Alto Douro

Denis Ostrovskii

Chalmers, Applied Physics, Condensed Matter Physics

P. C. Barbosa

University of Minho

M. M. Silva

University of Minho

M. J. Smith

University of Minho

Chemical Physics

0301-0104 (ISSN)

Vol. 345 1 32-40

Subject Categories

Other Engineering and Technologies

DOI

10.1016/j.chemphys.2008.01.034

More information

Latest update

2/28/2018