Spray deposited titanium oxide thin films as passive counter electrodes

Titanium dioxide (TiO2) thin films were deposited from methanolic solution onto fluorine doped tin oxide coated conducting glass substrates by spray pyrolysis technique. The electrochemical properties of TiO2 thin films were investigated using cyclic voltammetry, chronoamperometry, chronocoulometry and iono-optical studies, in 0.1N H2SO4 electrolyte. Performance of the films deposited at three different substrate temperatures, viz. 350, 400 and 450 °C is discussed in view of their utilization in electrochromic devices, as counter electrode. The magnitude of charge storage capacity, Q/t (4.75–6.13 × 10−3 mC/(cm2 nm)) and colouration efficiency (3.2–4.3 cm2/mC) of TiO2 rank these films among the promising counter electrodes in electrochromic devices.