Study On Preparation And Property Of TiO₂ Thin Films On Stainless Steel Substrate

TiO₂ thin films have been formed on stainless steel base by double glowdischarge technique and thermal oxidation method. The component, structure,electrochemical corrosion property and photocatalytic capability of the TiO₂ thinfilms have been studied. The main result has been obtained as follows:1. The result shows that the film consists of TiO and anatase TiO₂ under300℃thermal oxidation temperature, in the range of 400-600℃, the phase isanatase TiO₂, over 650℃the phase is rutile TiO₂. The surface layers formed onthe stainless steel substrate are duplex layers, composed of (Ti+O) thin filmand (Ti+O) diffusing layer. Ti and O content reduces gradually from surfacetoward substrate. It means the films have good adhesive strength with thesubstrate. With the increasing of oxidation temperature, the thickness of thethin films and diffusing layers increase.2. The electricity chemical corrosion property of the anatase TiO₂ andrutile TiO₂ thin films has been studied. The result shows that the corrosionresistance of the stainless steel after treated is enhanced both in 0.5M H₂SO₄ solution and 0.5M NaC1 solution, and the corrosion resistance of anatase TiO₂film is better than that of rutile TiO₂ film. The electricity chemical corrosionvelocity of anatase TiO₂ film, rutile TiO₂ film and stainless steel in 0.5MH₂SO₄ solution are 4.3×10^-3g/m²h, 4.54×10^-3g/m²h and 5.35x10^-3g/m²hrespectively. In 0.5M NaC1 solution the electricity chemical corrosion velocityof anatase TiO₂ film rutile TiO₂ film and stainless steel are 2.67×10^-3g/m²h,3.85×10^-3g/m²h and 1.07×10^-2g/m²h respectively.3. The photocatalytic capability of the anatase TiO₂ thin films have beenstudied by taking methylo range solution with 10mg/L concentration asimitated agent. The result indicates that the photo-catalyzed efficiency issignificantly improved by the anatase TiO₂ thin films under exposure ofultraviolet light.