Electrochromic properties of multi-layer WO3 / TiO 2 films made by electrochemical deposition

Abstract

Multilayer thin films of WO3/TiO2/FTO containning inorganic heterojunctions such as TiO2/FTO and WO3/TiO2 were prepared by electro-chemical deposition technique. From the cyclic voltammetry (CV) characteristics one can suggest that in the WO3/TiO2/FTO multi-layer films there is also W-doped TiO2structure, creating multi-heterojunctions of WO3, TiO2:W, TiO2and F-doped SnO2. Combining CV, time-current characteristic, in-situ transmittance spectra, the electrochromic performance of WO3/TiO 2/FTO was revealed. It is seen that the multi-layer electrochromic devices exhibited much larger electrochromic efficiency and faster response time than that of a standard single layer electrochromic device.