Spectroscopic study of poly(3-alkylthiophenes) electrochemically synthesized in different conditions

In this work, poly(3-alkylthiophenes) films were synthesized electrochemically in acetonitrile with LiClO4 or Et4NBF4 at 5 or 18 °C. The films were deposited on platinum plates, and the polymer as-prepared was referred to as-oxidized. The as-reduced polymer was obtained by subjecting the as-oxidized product to −1.70 V for 1 min. These various products were characterized by cyclic voltammetry, reflectance UV–Vis and Raman spectroscopy, and the results were used to estimate the ionization potential (I P), electron affinity (E.A.) and energy gap (E g) parameters. This study was possible because the Raman spectra demonstrated three structures (aromatic, radical cation and dication segments) which formed the P3MT and P3OT polymer chains.