Control of Amorphization of IrO2-Ta2O5/Ti Electrodes to Suppress Unwanted Side Reactions

Titanium electrodes coated with mixtures of IrO2 and Ta2O5 were prepared using different compositions of precursor solutions and at different thermal decomposition temperatures. The mixed oxide coatings became amorphous when the Ir content and/or thermal decomposition temperature decreased. The amorphization of the coating was effective to suppress anodic PbO2 deposition because of the increase in nucleation overpotential of PbO2 on the amorphous coating.