Corrosion protection of stainless steel plates in fuel cells environment by conducting polymers

The electrodeposition of polypyrrole and polyaniline has been performed in aqueous solutions of sodium saccharinate and sulphuric acid, respectively. The coatings were obtained by voltamperometric and galvanostatic methods. The corrosion behaviour of polypyrrole and polyaniline coated stainless steel (SS) in sulphuric acid medium was investigated by linear polarisation, open circuit potential and electrochemical impedance spectroscopy. The polyaniline coatings doped with sulphate anions (SO42−) showed more resistance to protect SS to corrosion than the polypyrrole coatings doped with saccharinate anions (C7H4NO3S−).