The kinetics of the reduction processes of PbO film in H 2SO 4: Part 3. Potential step method in Pb + Ca alloy electrodes

Abstract

Experimental results indicate that the process of reducing tetragonal PbO to Pb on Pb + Ca alloy electrodes is limited by the nucleation and growth of metallic lead and ion diffusion through the PbSO 4 layer. In the potential step to −850 mV, the process involves three-dimensional instantaneous nucleation and growth. The growth rate perpendicular to the metallic surface depends strongly on the reduction overpotential of tetragonal PbO. Some of the tetragonal PbO can be transformed into basic lead sulfates during the reduction process, similar to the results obtained with lead electrodes.