Currently, bipolar plate in PEM fuel cell that made from metal is used to replace with graphite materials. However, metal corrosion could be obtained from the acid conditions in fuel cell. Therefore, the prevention of metal corrosion is studied by coating with conductive polymers. In this research, monolayer polypyrrole (PPY) and bilayer polypyrrole/polyaniline (PPY/ PANI) were used to coat on stainless steel electrode by electrochemical methods. The target parameters were types of supporting electrolyte, monomer concentrations and electropolymerization methods. The results of pyrrole monomer concentration that synthesized by Cyclic voltammetry, Potentiostatic and Galvanostatic method were shown that corrosion resistivity was decreased with opposite to interfacial contact resistance (ICR) as increasing of monomer concentration. In aspect to supporting electrolyte types; sodiumdodecylsulfate, oxalic acid and sulfuric acid, it was found that the optimum conditions was synthesized PPY were Potentiostatic method at 0.6 V/SCE for 350 s containing 0.1 M of pyrrole monomer in oxalic acid that provided the best protection corrosion and low ICR value for first layer. The synthesized PANI in oxalic acid in the second layer (PPY/PANI) by Galvanostatic method at 0.1 mA for 600 s was indicated the corrosion protection efficiency and ICR value higher than monolayer. The results of morphology and composition of the PPY and PANI were confirmed by Scanning Electron Microscopy (SEM) and Fourier Transform Infrared Spectroscopy (FTIR), respectively.
