Electrochromic response of pulsed laser deposition prepared WO3–TiO2 composite film

Abstract

Electrochromic films of WO₃ with varying content of TiO₂, as a composite, were prepared via pulsed laser deposition method. The composite films exhibited cathodic electrochromism, which changed the original colorless appearance to a deep blue color. The films were examined for their structure, morphology, ultraviolet to visible photon absorption and chromic changes in electric fields. Pure WO₃ film showed stronger absorption at 600–800 nm wavelength of light than the composite films, which corresponds to blue color. The most intensive absorption wavelength of light could be modulated with TiO₂ inclusion, leading to a respective color change from dark blue to gem blue of the as-deposited WO₃–TiO₂–ITO glass. This work may serve as a basis for electrochromic windows and display device applications.