DETECTION OF SOLUBLE INTERMEDIATES DURING DEPOSITION AND REDUCTION OF LEAD DIOXIDE

The deposition and reduction of alpha-PbO2 from ethanoate solutions have been studied using a gold rotating ring disc electrode. In both cases a soluble Pb(IV) species has been detected at the ring. The formation of Pb(IV) during reduction as well as deposition is interpreted as evidence for a common Pb ... intermediate which undergoes rapid disproportionation to form Pb(II) and Pb(IV). The potential dependence of the ring current was interpreted as evidence that the Pb(IV) species detected was probably colloidal PbO2.