Sn-Containing Oxide Coatings: Formation, Composition, Electroanalytical and Catalytic Properties

Abstract

Sn-containing oxide coatings were prepared via plasma electrolytic oxidation (PEO) of Ti plate in the electrolytes with [SnII-EDTA]2- complex anions or SnO2 particles in the anode and anodic-cathodic modes. The coatings formed in electrolyte with SnO2 particles stabilized by SAS contain SnO2 and Sn0. In the electrolyte with [Sn-EDTA]2- complex anions, the SnO2-containing coatings were formed in the anodic mode while Sn0-containing ones were obtained in the anodic-cathodic mode. SnO2-containing structures formed in the electrolytes with [Sn-EDTA]2- anions are shown to be active in catalytic oxidation of CO into CO2 at temperatures above 350 °C. They can be the basis for the preparation of both carriers of catalytically active compounds and catalysts for redox reactions. Potentiometric tests showed that the Sn-containing PEO layers on titanium exhibit the most characteristic pH function for the metal oxide electrodes in the direct potentiometry and acid-base titration.