New Methods to Produce Electrocatalytic Lead (Iv) Dioxide Coatings on Titanium and Stainless Steel

Catalytic lead (IV) dioxide coatings have been produced on titanium and stainless steel 316 and 316L anodes. Good adherence of the lead (IV) dioxide coatings was obtained by depositing thin intermediate tin and nickel layers on titanium and steel respectively; this was achieved by procedures which have not been previously reported. On both the pretreated titanium and stainless steel substrates, the formation of alpha-lead (IV) dioxide (orthorhombic) and beta-lead (IV) dioxide (tetragonal) takes place, the beta form being the most abundant. Catalytic surfaces were produced at different current densities on both substrates. The lead (IV) dioxide surface stability was good in all cases. Anode performance was tested by means of the cyanide to cyanate oxidation reaction. The oxidation efficiency for the steel substrate anodes was better than the efficiency exhibited by titanium substrate anodes.