Solid State Ionics, Vol.116, No.1-2, 105-116, 1999
New counter electrode prepared as vanadium oxide and V/Ce oxide films: preparation and characterization
Vanadium oxide and mixed V/Ce-oxide films at 78, 55, 38, 32 atomic % of V were prepared via the sol-gel route from an aqueous colloidal solution of inorganic precursors. The influence of the added cerium precursor on their electrochemical, optical and structural properties was investigated by cyclic voltammetry (CV), X-ray analysis, LR spectroscopy and W-VIS techniques. The electrochemical stability of films was tested by CV measurements in 1 M LiClO4 in propylene carbonate electrolyte. The addition of CeO2 improved the poor stability of vanadium oxide films and enhanced their ion-charge capacity up to 30 mC/cm2 for thicknesses about 300 nm. The intercalation of Li+ ions in vanadium oxide and V/Ce-oxide films was followed by FT-IR spectroscopy performed at near-grazing incidence angle (NGIA) conditions in combination with CV measurements at potentials of - 1.5 V and + 2.0 V (vs. Ag/AgCl). The observed shift of V-O-v vibrations in the IR spectra confirmed the intercalation of Li+ ions.
Keywords:MIXED CEO2/SNO2 COATINGS;THIN-FILMS;ELECTROCHEMICALPROPERTIES;OPTICAL-ABSORPTION;PENTOXIDE GELS;V2O5;CEO2