In this work we used IR spectroscopy as an analytical tool to estimate the
degree of Li+ intercalation in crystalline V2O5 films. Films were prepared
from a V-oxoisopropoxide precursor, using a sol-gel mute. After the deposit
ion of the films by dip-coating, the films were heated at 300 degrees C for
60 min.
A polaron absorption extending from the visible and near IR and terminating
at 2000 cm(-1) was observed in insitu FT-IR reflection-absorption (LO mode
s) and ex-situ FT-IR absorbance (TO) spectra of V2O5 films. Results showed
that the intensity of the polaron absorption depends on the amount of inter
calated Li+ ions and therefore the applied potential. The variation in the
intensity of the polaron absorption was accompanied by the reversible chang
es of the TO and LO vibrational modes in the ex-situ and in-situ IR spectra
of V2O5 films. (C) 1999 Elsevier Science Ltd. All rights reserved.