Conducting Polyaniline/Au Nanorods Composite Film for High-Performance Electrochromic Device

Abstract

Conducting polymers are promising candidate materials in next-generation electrochromic applications due to their multicolour changes, flexible and large-scale production capability; however, poor cycling stability and relatively low optical modulation limit their widespread application. In this article, a simple electrochemical deposition method is used to create a polyaniline (PANI)/Au nanorods composite electrochromic film on ITO glass as an electrode. This PANI/Au nanorods composite film has better electrochromic properties than the straight PANI film. Moreover, the electrochromic device (ECD) was successfully fabricated by PANI/Au nanorods composite film as anode and poly(3,4-ethyloxylthiophene) as the cathode. This resultant device exhibits perfect electrochromic performance, including higher optical modulation (56%), a faster response time (0.6 s for bleaching and 0.9 s for colouring) and good cycling stability (sustained 85% after 6750 cycles). Notably, the geometric structure of the film is formed by the Au nanorods coated with PANI, which not only can provide transport channel and ion storage space but also improving the conductivity. In addition, the composite structure can provide larger surface area and benefit the electrolyte ions insertion and extraction from the composite electrode film. The rational design of stacking nanocomposites on electrodes may be a useful method for fabricating high-performance ECDs.