Investigation of photocatalytic activities of nanostructured nitrogen dopedTiO2 thin films under visible light prepared via sol-gel method on type 304stainless steel

Nowadays photocatalyst materials especially TiO2 are widely used in different fields andindustries such as self-cleaning surfaces, water purification, solar cells and biomaterials. A greatdrawback about TiO2 as a practical photocatalyst material is its wide band gap energy. TiO2 canonly cause photocatalytic reactions under UV light; therefore its indoor applications as aphotocatalyst material are restricted due to the lack of UV light in such places. In this research,nanostructured nitrogen doped TiO2 films were prepared on type 304 stainless steel by sol-gelmethod using an airbrush to apply the sol on the surface of the steel, then samples were calcined atvarious temperatures between 400°C and 600°C. Grazing incidence XRD and conventional XRDwere used to determine the phase composition of the samples, the thickness of films were measuredby ellipsometry, also UV–Vis spectra analyses (in diffuse reflectance mode) was utilized to estimatetheir band gap energy. Results showed that films thickness was 150nm and due to doping of nitrogeninto TiO2 structure, its band gap energy reduced to 2.85 eV which was completely shifted towardvisible region. Measurement of methylene blue degradation under visible light was used toinvestigate the photocatalytic activities of thin films. The sample that was calcined at 500°C showedthe best photocatalytic performance and it degraded 22% of methylene blue after 2 hours undervisible light

Investigation of photocatalytic activities of nanostructured nitrogen dopedTiO2 thin films under visible light prepared via sol-gel method on type 304stainless steel Keywords:

Visible light activated TiO2 , Nanostructured thin film , Photocatalysis , Sol spraying