INFLUENCE OF COBALT ON THE OXYGEN DEPOLAR IZATION AT PB AND PB-AG ALLOYING ANODES

In this study lead and lead silver alloys are anodic polarized galvano staticly for 20 h in Ca2+-containing electrolyte, so that Co(x)O(y) do ped leaddioxide surface layers are produced. Afterwards these material s are investigated by anodic polarization in 200 g/l sulfuric acid sol ution under galvanostatic conditions. Then current density - potential - curves are measured, the Tafel-plots are calculated and compared wi th a lead anode, which is polarized without Ca2+-ions. The optimal con ditions for a dense and mechanical strong doped oxide layer are establ ished. The obtained anodes show potential of oxygen formation 120 m V lower than a lead anode. A summary of the effects of silver and cobalt is not detected.