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

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.