Coupling of crystalline colloidal arrays with intrinsically conductive polymers: Reflection-type electrochromic devices

► Crystalline colloidal array composed of polystyrene particles. ► Multilayered device construction with electrochromic layer. ► Selective optical properties by coupling electrochromic response with optical bandgap. The attenuation of the reflected light from a polystyrene (PS) polymerized crystalline colloidal array (PCCA) is achieved through the electrochemical switching of the electrochromic material polyaniline-poly(2-acrylamido-2-methyl-1-propanesulfonicacid) (PANI-PAMPS). For this purpose, layered electrochromic devices (ECDs) were fabricated that employed a PS PCCA film, acting as both a reflecting substrate and polymeric electrolyte, and the conducting polymer PANI-PAMPS, which served as the electrochromic layer. The resulting ECDs exhibited the attenuation of reflectance peak at the stop band position of the PCCA with a 3% of reflectance contrast ratio.