The Influence of Oxidizing Agent in the Chemical Deposition of Polypyrrole on Lead Alloy Surface

Polypyrrole (PPy) layers were deposited on lead metallic surface using hydrogen peroxide or benzoyl peroxide as oxidizing agent associated with different types of dopants: phosphoric acid, stearic acid and dodecylbenzene sulfonic acid. Lead alloy was chosen because of its importance in energy industrial application and also because its primary source of extraction is running out, there is an increasingly urgent need to extend its life cycle. For the in situ chemical deposition of PPy, it was considered the combination of only one oxidizing agent and one dopant, being the experiment performed with the combination of these reagents. The morphology and corrosion protection effectiveness of the PPy layer was studied by Scanning Electron Microscope (SEM), Open Circuit Potential (OCP) and Potentiodynamic Polarization. The experimental results demonstrate that PPy layer was effectively formed as a coating layer and Hydrogen Peroxide performed better and consistent protection efficiency when compared to Benzoyl Peroxide.