Improvement in corrosion protection properties of TiO2 coatings by chromium doping

A series of chromium-doped TiO2 coatings was prepared for corrosion protection of 316L stainless steel substrates. The morphology, crystalline phase and composition of the coatings were systematically investigated. The corrosion protection performances of the coatings in the presence and absence of simulated sunlight illumination were evaluated through electrochemical measurements. The chromium-doped TiO2 coatings showed a remarkable improvement in photogenerated cathodic protection properties under illumination. In addition, during a long-time dark immersion process, the chromium-doped TiO2 coatings could provide an active corrosion protection for metal substrates due to the self-healing property of chromium ions.

► A series of chromium-doped TiO2 coatings has been prepared and characterized.
► Cr(III) improves photogenerated cathodic protection properties of TiO2 coatings.
► Cr(III) and Cr(VI) provide self-healing properties for the TiO2 coated metal.