Poly(3-Octylthiophene) and Poly(3-Octylthiophene)/TiO₂-Coated on Al1050: Electrosynthesis, Characterization and Its Corrosion Protection Ability in NaCl Solution

Abstract

In this study, 3-octylthiophene (3OT) and its nanocomposites with TiO2(3OT/TiO2) were electrochemically synthesized in different initial monomer concentrations (50, 75, 100, and 150 mM) in 0.1 M tetraethylammonium tetrafluoroborate (TEABF4)/acetonitrile (CH3CN) on a glassy carbon electrode (GCE). The best modified electrodes, which were taken from the optimum conditions of redox behaviors, were also electropolymerized in 0.5 M oxalic acid/acetonitrile (CH3CN) solution on Al1050 electrode. The modified Al1050 electrodes were characterized by optical microscope, FTIR-ATR, SEM-EDX, and EIS. The optimum conditions of the electrocoated P(3OT)/Al1050 and P(3OT)/TiO2 nanocomposites on Al1050 electrode were investigated for corrosion performances against 3.5% NaCl solution. The corrosion tests were performed by EIS and Tafel extrapolation plots together with the equivalent circuit model of Rs(Qc(Rc(QpRct))). P(3OT)/TiO2 nanocomposite films showed higher protection efficiency (PE = 89%) than P(3OT) films (PE = 81%). The P(3OT)/TiO2 nanocomposite films coated on Al1050 electrodes may be used in industrial applications of corrosion protection against salt water.