Electrochromic WO3 films prepared by a new electrodeposition method

Tungsten oxide (WO3,) films with good electrochromic properties were prepar ed by a new electrodeposition method. The structural properties were charac terized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The electrochemical and optical properties were measured by cyclic voltamme try (CV) and spectral optical transmittance and reflectance methods. The fi lms an amorphous or microcrystalline depending on the post-annealing temper atures, both of them having a very smooth surface. Different electrochromic properties can be obtained for amorphous and microcrystalline films, with the amorphous one showing good absorption modulation in the visible range a nd microcrystalline one showing obvious reflectance change in the near-infr ared range. Good durability of the deposited films was observed which was v ery important for the practical applications. (C) 2000 Published by Elsevie r Science B.V. All rights reserved.