Preparation of porous oxide layers by oxygen bubble templated anodic deposition followed by galvanic displacement

In recent years, there has been considerable interest in the hydrogen bubble-templated electrodeposition of porous metals (1). In this process, an electrolysis performed at high cathodic current density causes simultaneous metal ion reduction and hydrogen evolution, leading to the formation of highly porous metal films on the cathode, normally consisting of nanocrystals. Our group has recently shown that a symmetric anodic process can be used for producing porous layers of PbO2 which, due to their enhanced surface area, exchange much larger charges than compact layers, when cycled in H2SO4 solutions (2,3).....