Ag and SnO2 co-sensitized TiO2 photoanodes for protection of 304SS under visible light

Highlights: • TiO2 nanotubes were decorated with Ag and SnO2. • Synthesis of the functionally most useful composite is described. • With 0.10 M AgNO3 and 20-cycle SnO2 can prepare the most functional composite. • The co-sensitization suppresses the recombination of electron-holes pairs. - Abstract: Ag and SnO2 co-sensitized TiO2 photoelectrodes were prepared by photoreduction deposition and sol–gel method. The morphology, crystalline phase, composition and optical absorption property of the composites were systematically investigated. The corrosion protection performances of the composites in the presence and absence of illumination were evaluated through electrochemical measurements. The results indicate that the co-sensitization of Ag and SnO2 shifts light absorption of TiO2 to the visible light region and enhances the separation efficiency of photogenerated charges. The co-sensitized TiO2 photoelectrodes exhibit highly effective photogenerated cathodic protection properties for stainless steel