Stable and multicolored electrochromic device based on polyaniline-tungsten oxide hybrid thin film

Abstract

In this study, tungsten oxide (WO3) film was used to enhance the stability as well as the performance of electrochromic window (ECW) based on famous conductive polymer-polyaniline (PANI). PANI and WO3 films were prepared and employed to fabricate hybrid ECW with an unprecedented stability (over 1000 cycles) and more colorful device with various color (green, blue, and violet of neat PANI, and deep blue of WO3). The multicolor nature of device maybe due to the simultaneous change of the band gaps of both PANI and WO3 in the reversible redox process. The present device based on the PANI-WO3 hybrid film shows superior electrochromic performance compare with that of neat PANI film. A short switching time (1.5 s each for colored and bleached processes), a high coloration efficiency (195 cm2 C−1), a prolonged lifetime (over 1000 cycles) and multicolor are the significant advantages of the PANI-WO3 hybrid film. The result indicates that ECW based on PANI-WO3 hybrid film is great candidate for next generation of electrochromic device such as electronic display and smart window.