Morphology of (Ru-Ti-Sn) mixed-oxide coatings

Noble-metal-oxide-based coatings have successfully replaced many of the conventional anode materials in industrial electrochemical processes. The performance characteristics of these mixed-oxide electrodes have been found to be improved by the inclusion of non-noble-metal-oxide components. Of these, the addition of SnO2 to RuO2-TiO2 has attracted much attention. In the present paper, the morphology change imparted by gradual replacement of TiO2 by SnO2 from the RuO2-TiO2 (30/70) coatings is reported. Scanning electron microscopic examination and porosity determination reveal that significant modifications take place in the surface structure, and the surface layer tends to become compact at SnO2 concentration above 30 mol % SnO2.