Sprayed CeO2 thin films for electrochromic applications

Cerium dioxide (CeO2) thin films were prepared by spray pyrolysis using hydrated cerium chloride (CeCl3. 7H(2)O) as source compound. The films prepared at substrate temperatures below 300 degreesC were amorphous, while those prepared at optimal conditions (T-s = 500 degreesC, s = 5 ml/min) were polycrystalline, cubic in structure, preferentially oriented along the (200) direction and exhibited a transmittance value greater than 80% in the visible range. The cyclic voltammetry study showed that films of CeO2 deposited on ITO pre-coated glass substrates were capable of charge insertion/extraction when immersed in an electrolyte of propylene carbonate with 1M LiClO4. These films also remained fully transparent after Li + intercalation/deintercalation. (C) 2001 Elsevier Science B.V. All rights reserved.