(CEO2)(X)-(TIO2)(1-X) - COUNTER ELECTRODE MATERIALS FOR LITHIUM ELECTROCHROMIC DEVICES

Since 1989, (CeO2)(x)-(TiO2)(1-x) have been considered as possible cou nter electrode materials for electrochromic devices using lithium cond ucting electrolytes and WO3 as electrochromic material. The electroche mical behaviour of thin films of these materials depends on the struct ure of the films and on the electrolyte composition. According to X-ra y diffraction data, the films seemed to be composed of an amorphous ma trix of TiO2 including nanocrystallites of CeO2.After a short review o f the data previously obtained, new data obtained on materials made up by using either sol-gel processes (Ti(OPri)(4) + Ce(OPri)(4) or CeCl3 or Ce(NH4)(2)(NO3)(4)) or sputtered from oxide targets are presented. The influences of the nanocrystalline structure, of the electrolyte t ype (polymer based solid electrolyte or liquid organic electrolyte) an d of the water content are discussed.