Electropolymerization of Polypyrrole and Polypyrrole-ZnO Nanocomposites on Mild Steel and Its Corrosion Protection Performance

Polypyrrole (PPy) and Polypyrrole-ZnO (PPy-ZnO) nanocomposites were electrodeposited on mild steel and its corrosion protection ability was studied by Tafel and Impedance techniques in 3.5% NaCl solution. Pure Polypyrrole film was not found to protect the mild steel perfectly but the coating with nano-sized ZnO (PPy-ZnO) has dramatically increased the corrosion resistance of mild steel. Electrochemical Impedance Spectroscopy (EIS) measurements indicated that the coating resistance (R(coat)) and corrosion resistance (R(corr)) values for the PPy-ZnO nanocomposite coating was much higher than that of pure PPy coated electrode. (C) 2011 Wiley Periodicals, Inc. J Appl Polym Sci 121: 3159-3166,