PSS-free PEDOT and PEDOT/graphene transparent films: Synthesis, characterization and electrochromism

PSS-free poly-ethylenedioxythiophene (PEDOT) was synthesized by the chemical polymerization of ethylenedioxythiophene (EDOT) at an immiscible liquid/liquid interface. The unique characteristics of the synthetic route allows the simultaneous preparation and processing of the polymer as a thin, transparent, flexible and conductive film self-assembled at the liquid interface. PEDOT/graphene nanocomposite thin films were also prepared, in which both the components were chemically synthesized together, starting from EDOT and benzene, respectively. The films were easily deposited over different solid substrates, plastics included, and characterized by spectroscopic, microscopic and electrochemical techniques. The potentiality of the films in applications requiring electrochromism was demonstrated, and the electrochromic parameters indicated excellent reversibility, response times lower than 10 s and high coloration efficiency.