Electrochromic device of PEDOT–PANI hybrid system for fast response and high optical contrast

An organic–organic hybrid system composed of the polyaniline (PANI) and poly-(3,4-ethylenedioxythiophene) (PEDOT) with controlled thickness was developed successfully in order to realize synergetic effects in electrochromic (EC) properties such as optical contrast and color-switching rate. From the UV transmittance spectra, we found that the optical contrast (Δ%T) was enhanced up to 6–72% at the wavelength of 580 nm compared with the previous PANI–PEDOT ECDs. Furthermore, the optimized ECD showed an extremely fast response time of less than 160 ms. It is therefore concluded that such a complementary full .cell system of PEDOT–PANI ECD is applicable as an optical device.