Spectroscopic and structural studies of di-ureasils doped with lithium perchlorate
Artikel i vetenskaplig tidskrift, 2007

Di-urea cross-linked POE/siloxane hybrid ormolytes (di-ureasils) doped with a wide concentration range of lithium perchlorate trihydrate (LiClO4 center dot 3H(2)O) (200 >= n >= 0.5, where n expresses the salt content in terms of the number of ether oxygen atoms per Li+ ion) have been analysed by Fourier transform infrared and Raman (FT-IR and FT-Raman, respectively) spectroscopies and X-ray diffraction (XRD). The results obtained lead us to conclude that the xerogels with n >= 5 are totally amorphous. At n <= 1 free salt is observed. "Free" ClO4- ions appear to be the main charge carriers at the conductivity maximum located within the 25 <= n <= 8 composition range of this family of ormolytes. At n = 15 ClO4- ions coordinated in mono/tridentate (C-3v symmetry) and bidentate (C-2v symmetry) configurations were detected. In salt-rich samples with n < 15 there is a marked tendency for ionic association. The resulting decrease that occurs in the concentration of "free" ions is consistent with the observed significant decrease of the ionic conductivity. The analysis of the "amide I" and "amide II" regions provided solid proof that the Li+ ions bond to the urea carbonyl oxygen atoms over the entire range of salt concentration studied. (c) 2007 Elsevier Ltd. All rights reserved.

SPECTRA

Di-ureasils

ELECTROLYTES

ORGANICALLY MODIFIED SILICATES

ION-CONDUCTING ORMOLYTES

TEMPERATURE

INFRARED

FF-Raman

solid polymer electrolytes

POLYMERS

STATE

ASSOCIATION

sol-gel process

COMPLEXES

FT-lR

BATTERIES

Författare

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, Teknisk fysik, Kondenserade materiens fysik

P. B. Tavares

Universidade de Tras-os-Montes e Alto Douro

P. C. Barbosa

Universidade do Minho

M. M. Silva

Universidade do Minho

M. J. Smith

Universidade do Minho

Electrochimica Acta

0013-4686 (ISSN)

Vol. 53 1466-1475

Ämneskategorier

Annan teknik

DOI

10.1016/j.electacta.2007.04.061