Electrochemical co-polymerization of a novel fluorene derivative with 3,4-ethylenedioxythiophene

The co-polymerization of a novel fluorene derivative, N-(9H-fluoren-9-ylidene)benzamine (FBA), with 3,4-ethylenedioxythiophene (EDOT) was successfully achieved in acetonitrile via direct anodic oxidation of the monomer mixtures both on platinum and indium-tin oxide working electrodes. The characterization of copolymer films, poly(EDOT-co-FBA), was carried out utilizing electrochemical, spectroelectrochemical, electrochemical impedance (EIS), and FT-IR techniques. It is found that poly(EDOT-co-FBA) films which were synthesized with a feed ratio of FBA/EDOT 5/2 via both potentiodynamically and potentiostatically, had different properties than that of electrochemically prepared poly(3,4-ethylenedioxythiophene) (PEDOT) film. Spectroelectrochemical investigations revealed that copolymer films exhibit relatively lower band gap (1.63 eV) than that of polyfluorenes. Electrochemical impedance spectroscopy (EIS) was also employed to investigate both the resistance and capacitance properties of copolymer coatings.