Pitting corrosion protection of low nickel stainless steel by electropolymerized conducting polymer coating in 0·5 M NaCl solution

Conducting polymers of polyaniline (PANi) and poly(o-phenylenediamine) (PoPD) were electropolymerized by cyclic voltammetric technique on low nickel stainless steel (LN SS) in H2SO4solution containing aniline and o-phenylenediamine monomers. The coatings were characterized by Fourier transform infrared spectroscopy, UV-visible and scanning electron microscopic techniques and the results are discussed. The corrosion protective properties of PANi and PoPD coatings on LN SS in 0·5 M NaCl were evaluated using potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) techniques. The potentiodynamic polarization and electrochemical impedance spectroscopic results indicate that the PoPD coating inhibits the corrosion of LN SS in 0·5 M NaCl solution more effectively than PANi.