Electrodeposition of lead dioxide on carbon substrates from a high internal phase emulsion (HIPE)

PbO2 coatings on carbon electrode substrates were produced by anodic electrodeposition from a stationary high internal phase emulsion ( HIPE) with the bath components added in the water phase. The deposits have a distinct structure consisting of 10 - 50 mum high pyramidal aggregates, pitted with smaller pores. This is attributed to the growth of the deposits through the aqueous network of the HIPE emulsion that is, through the tortuous paths formed by its interconnected water cavities. The coatings thus produced are characterised by enhanced electrochemical activity towards the PbO2/ PbSO4 transformation.