Preparation and characterization of Mo- and Sb: Mo-doped SnO2 sol-gel-derived films for counter-electrode applications in electrochromic devices

Abstract

Mo-doped and Mo:Sb-doped SnO₂ were made via the inorganic sol-gel route from the corresponding metal chloride precursors and the films were deposited by dip-coating technique. Films with a thickness of 100–170 nm were made by single dipping and the corresponding charge capacities were in the range 6–11 mC cm^–2. The films retained their high optical transparency in the reduced and oxidized state and were promising counter-electrodes in electrochromic devices with transmissive modulation. This was demonstrated by using the films as a counter-electrode in an electrochromic device employing an electrochromic phosphotungstic acid/titanium oxide xerogel film and 0.001 mol dm^–3 HClO₄ aqueous electrolyte.