Electrochemical polymerization and characterization of polypyrrole on Mg-Al alloy (AZ91D)

We report the formation of polypyrrole (PPy) coatings on Mg alloy AZ91D from aqueous solutions of a dicarboxylic organic acid salt by cyclic voltammetry (CV) method. The polymeric films of PPy are directly coated onto AZ91D substrates without any pretreatment or intermediate steps. The electrochemically formed PPy films were characterized by Fourier Transform Infrared Spectroscopy (FT-IR), X-Ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS). Electrochemical impedance spectroscopy (EIS) measurements demonstrate a good corrosion protection.