Manganese dioxide as a potential cathodic reactant in corrosion of stainless steels

Abstract

Biofilms of leptothrix discophora SP-6, grown on 316L stainless steel (SS), ennobled the open circuit potential to 410 mVSCE. X-ray Photoelectron Spectroscopy (XPS) identified MnO2 was studied using electroplated SS. Plated MnO2 was reduced amperometrically. The process was interrupted at different reduction stages. XPS analysis of remaining oxides showed that MnO2 was reduced through MnOOH to Mn2+. We conclude that biomineralized MnO2 may increase corrosion rates by serving as a cathodic reactant.