Low-temperature liquid phase deposited TiO2 films on stainless steel for photogenerated cathodic protection applications

The low-temperature synthesis of anatase TiO₂ films was an imperative requirement for their application to corrosion prevention of metals. In this paper, a liquid phase deposition (LPD) technique was developed to prepare TiO₂ films on SUS304 stainless steel (304SS) at a relatively low temperature (80 °C). The as-prepared films were characterized using scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectroscopy and X-ray photon spectroscopy (XPS). It was observed that a dense and crack-free anatase TiO₂ film with a thickness about 300 nm was obtained. The film contained some fluorine and nitrogen elements, and the amounts of these impurities were greatly decreased upon calcination. Under the white light illumination, the electrode potential of TiO₂ coated 304SS rapidly shifted to a more negative direction. Moreover, the photopotential of TiO₂/304SS electrode showed more negative values with increased film thickness. In conclusion, the photogenerated cathodic protection of 304SS was achieved by the low-temperature LPD-derived TiO₂ film.