Studies of the Surface Reaction Mechanisms of Pb-3 wt%Sn-0.5 wt%Ag Anode in CrO 3 Solutions

Abstract

This work examines the change of surface properties and the reaction process of lead alloy anode in CrO3 solution under conditions of high current density, bymeans of SEM, EDX, XRD, electrochemical test and Raman spectroscopy, for understanding the corrosion mechanism of lead alloy anode. In the initial oxidation stage of lead alloy anode, the diffraction peaks of monoclinic PbCrO4 and PbO are clearly shown in the XRD spectrum of the lead alloy surface. With increasing reaction time, PbCrO4 and PbO diffraction peaks are weakened and those of lead dioxide strengthened. Cyclic voltammetry reveals that the electrode potential change is among Pb, PbO, PbCrO4, PbO1+x (0