An electrochemically and optically stable electrochromic polymer film based on EDOT and 1,2,3,4-tetrahydrophenazine

Abstract

In this work, 3,4-ethylenedioxythiophene (EDOT) and 1,2,3,4-tetrahydrophenazine based donor-acceptor-donor type monomer (EBE) was synthesized, electropolymerized and the resulting polymer film (P(EBE)) was investigated in terms of its electrochemical and spectroelectrochemical properties. The polymer film showed excellent electrochemical stability upon 1000 switchings by saving almost full of its electroactivity. Moreover, 95% of the optical contrast was maintained after 500 switchings. The optical band gap value was calculated using Tauc Plot method and found as 1.5 eV. P(EBE) film revealed multichromic behaviour between its fully neutral and oxidized states; dark cyanish-green at - 0.8 V, more green at - 0.5 V and transmissive green beyond 0.6 V potentials. Finally, a dual type electrochromic device (ECD) was constructed with P(EBE) and poly(3,4-ethylenedioxythiophene) (PEDOT) films and the spectroelectrochemical behaviour of ECD was depicted.