Abstract
Iridium oxide films prepared by thermal oxidation of iridium carbon composite films show persistent electrochromic (EC) behavior in a propylene carbonate solution containing 1 M LiClO4 and 0.8–1.0 wt% water. By treatment in aqueous 0.5 M H2SO4 before hand, the EC behavior of the film has been improved. The charge capacity and corre-sponding transmission variation of the film were 9.5 mC/cm2 and in the range from 0.69 to 0.50, respectively.