Anti-Corrosion Performance of Conductive Copolymers of Polyaniline/Polythiophene on a Stainless Steel Surface in Acidic Media

Abstract

The composite conductive copolymers of polyaniline/polythiophene (Pani/PTH) were successfully prepared by an electrochemical method on a stainless steel surface containing both aniline and thiophene in a 0.3[Formula: see text]mol/L oxalic acid solution. The anti-corrosion performance of the Pani/PTH on stainless steel surfaces was investigated in acidic media by polarization curve analysis and electrochemical impedance spectroscopy (EIS). Additionally, the surface morphology of Pani/PTH composite conductive copolymers was observed by scanning electron microscopy (SEM). The results showed that the Pani/PTH copolymers strongly adhered to the surface of the stainless steel. Compared with that of bare stainless steel, composite conductive copolymers of Pani/PTH on the stainless steel surface provided good anti-corrosion behavior; additionally, the corrosion potential could be improved by approximately 400[Formula: see text]mV, while the current density decreased by two orders of magnitude in the corrosion media. The above results were in accordance with the SEM characterization results. The SEM spectrum showed that the Pani/PTH film had a uniform, dense and shiny structure, so it had better anti-corrosion behavior.