The electrochromic characteristics of titanium oxide thin film electrodes

Titanium dioxide in its anatase form may react with lithium by a reversible intercalation process. This process is accompanied by a marked colour change, so that TiO2 is of interest for the development of electrochromic displays. The electrochromic properties of thin film electrodes, obtained by a deposition on a tin oxide coated glass substrate of a TiO2 dispersion in polyvinylalcohol, are examined in this work. The results show that the rate of the electrochromic process is controlled by the diffusion of the Li+ ions throughout the TiO2 lattice. Consequently, it is convenient to drive the electrochromic process with potentiostatic pulses and, effectively, under these conditions many cycles with initial good colour contrast and efficiencies which approach 100%, have been obtained with the TiO2 thin film electrodes.