The corrosion behaviours of polyaniline coated stainless steel in acidic solutions

Polyaniline (PANI) coating on stainless steel (SS) using oxalic acid as supporting electrolyte was obtained by using cyclic voltammetry technique. The corrosion performances of these PANI coated electrodes (SS/PANI) were determined in 0.05 M sulphuric acid and in 0.1 M hydrochloric acid solutions with electrochemical impedance spectroscopy and anodic polarization curves. The results clearly showed that SS/PANI immersed in sulphuric acid appeared to have better protective effect on the corrosion of SS than that of hydrochloric acid. The PANI coating was found to be stable and protective for extended immersion period in 0.05 M H2SO4.