ELECTROCHEMICAL KINETICS OF ANODIC LAYER FORMATION AND REDUCTION ON ANTIMONY AND ANTIMONIAL LEAD

The cyclic voltammetry of lead, antimony and lead + antimony binary al loys has been studied in 0.5 M H2SO4 solution at 25-degrees-C between the hydrogen and oxygen evolution potentials and over narrower potenti al regions. This investigation, together with systematic variation of the scan rates and the positive or negative reversal potential, has re vealed more details of the oxidation and reduction processes which giv e further insight into the nature of reactions in the lead-acid batter y. Voltammetry data were interpreted taking into account nucleation an d growth models, thermodynamic data and the electronic properties of t he surface compounds in the potential region of species containing Pb( II), Pb(IV) and Sb(III). The conditions under which PbO and PbO2 forma tion can be seen in the positive sweep have been determined.