Synthesis and Characterization of Dithienothiophene, Bithiazole and Thiophene Containing Polymer

Synthesis of comonomer, possessing 4,4'-dinonyl-2,2'-bithiazole and 3,5-diphenyldithieno[3,2-b;2′,3′-d]thiophene (T-NBT-Ph2DTT-NBT-T) units, was achieved using Stille cross coupling reaction. Its electropolymerization was conducted in acetonitrile, containing 0.1 M NaClO4 + 0.1 M LiCIO4 (MCIO4). Properties of the polymer film, obtained P[T-NBT-Ph2DTT-NBT-T], were characterized by electrochemical techniques. Effect of the polymerization charge on the redox behavior of the polymer film was investigated, and the film was further characterized by UV-visible spectrophotometric measurements. Corresponding electrical equivalent circuit was applied to the experimental electrochemical impedance spectroscopy (EIS) data to explain the parameters of each element and the interface of the Pt/P[T-NBT-Ph2DTT-NBT-T]/MCIO4 system. The band gap of the polymer was obtained as 1.86 eV by in situ spectroelectrochemical measurements. Good stability in the oxidized state was verified experimentally. Molecular orbitals and electropolymerization of the comonomer were investigated at DFT level.