Synthesis and characterization of a new soluble conducting polymer and its electrochromic devices

A new polythiophene derivative was synthesized by both chemical and electrochemical oxidative polymerization of 1-(perfluorophenyl)-2,5-di(2-thienyl)-1H-pyrrole (FPTPy). The structures of both the monomer and the soluble polymer were elucidated by nuclear magnetic resonance (1H-NMR) and fourier transform infrared (FTIR). Polymer of FPTPy was also synthesized via potentiostatic electrochemical polymerization in acetonitrile (AN)/NaClO4/LiClO4 (0.1 M:0.1 M) solvent–electrolyte couple. Characterizations of the resulting insoluble polymer were performed by cyclic voltammetry (CV), FTIR, scanning electron microscopy (SEM) and UV–Vis Spectroscopy. Four-probe technique was used to measure the conductivities of the samples. Moreover, the spectroelectrochemical and electrochromic properties of the polymer film were investigated. In addition, dual type polymer electrochromic devices (ECDs) based on P(FPTPy) with poly(3,4-ethylenedioxythiophene) (PEDOT) were constructed. Spectroelectrochemistry, electrochromic switching and open circuit stability of the devices were studied. They were found to have good switching times, reasonable contrasts and optical memories.