Liquid phase deposition (LPD) of TiO2 thin films as photoanodes for cathodic protection of stainless steel

In this paper, the liquid phase deposition (LPD) technique was developed to prepare TiO2 thin films on ITO conducting glass applied to the photogenerated cathodic protection of SUS304 stainless steel (304SS). The results showed that a dense and crack-free anatase TiO2 film with a thickness of 800 nm was prepared from the LPD process at 80 °C for 3 h. Moreover, the TiO2 films exhibited a decrease in crystal preferential orientation and an increase in optical band gap energy when heat treated at 300 °C and 500 °C. In addition, the results of the photoelectrochemical measurements showed that the photopotential of the as-deposited TiO2 film was stabilized at about −200 mV, whereas those of the films subjected to heat treatment at 300 °C and 500 °C were stabilized at −400 mV and −460 mV, respectively. It was indicated that both the as-deposited and the heat treated LPD-derived TiO2 films exhibited sufficiently negative electrode potential under illumination, which could serve as the photoanodes for effective cathodic protection of 304SS.

► The anatase TiO2 films were obtained on ITO substrate by liquid phase deposition.
► The TiO2 films were dense and crack-free with a thickness of about 800 nm.
► The TiO2 film exhibited an effective photogenerated cathodic protection for 304SS.