Selenophene-co-thianaphthene films have been successfully electropolymerized by direct oxidation on platinum electrode in acetonitrile solution containing a 0.1 mol L-1 TBATFB as supporting electrolyte. The obtained material films have one redox couple with enhanced redox capacity. The investigated properties of copolymers strongly depended on the polymerization conditions. Band gap energies of homo- and copolymer films are calculated and the values are between 1.91 and 2.02 eV. The electrical conductivity measurements of co/polymers are effectively recorded using a four-probe technique and are generally increased with increasing temperature. FTIR spectra exposed that bands of the copolymers are retained in the spectra of homopolymers. Furthermore, the bands of the doped copolymers are shifted to lower energies with respect to the as-prepared ones. This shift indicates bond weakening due to the removal of electron density from pi-bonding orbitals due to the co/polymer oxidation (C) 2017 Elsevier B.V. All rights reserved.