Corrosion Performance of Polypyrrole Coated Type 304 Stainless Steel for Bipolar Plates of Proton Exchange Membrane Fuel Cell

Polypyrrole coating doped with dodecylsulfate anions was electrodeposited by cyclic voltammetry and constant current technique on type 304 stainless steel used for bipolar plates of a proton-exchange membrane fuel cell from a basic solution of 0.2M pyrrole monomer solution containing dodecylsulfate sodium as supporting electrolyte. The morphology and corrosion performance of Ppy coated samples were investigated. Microscopic observations showed that the polypyrrole synthesized by constant current technique present a more dense constitution. Electrochemical measurements in 0.1M HCl solution showed that the polypyrrole synthesized by constant current technique provided better protection for the stainless steel.