Development of visible light activated TiO2 thin films on stainless steel via sol spraying with emphasis on microstructural evolution and photocatalytic activity

作者：Momeni Mansour; Golestani Fard Farhad^*; Saghafian Hasan; Barati Nastaran; Khanahmadi Amirhossein

来源：Applied Surface Science, 2015, 357: 1902-1910.

DOI：10.1016/j.apsusc.2015.09.122

• Visible light activated TiO2
• N doped TiO2
• Sol spraying
• Thin film
• Photocatalysis
• Stainless steel

Visible light activated nitrogen doped TiO2 thin films were developed on 304 stainless steel by sol spraying method using a common painting airbrush. Thin films with different thickness were prepared and calcined at various temperatures from 400 to 600 degrees C. The samples were studied using ellipsometry, XRD, GIXRD, XPS, DRS, SEM and FESEM. Photocatalytic activities of the films were investigated by measuring their ability to degrade methylene blue solution under visible light irradiation. Results revealed that uniform nanostructured films with a thickness range of 29-150 nm were successfully prepared on stainless steel by sol spraying. Doping nitrogen into TiO2 structure restricted the crystallite growth of anatase phase and reduced the band gap energy to 2.85 eV and therefore, activated TiO2 in visible light region. Increasing calcination temperature not only promoted crack formation in thin films, but also encouraged Fe diffusion from substrate into thin films structure. However, the N doped TiO2 film calcined at 500 degrees C with a thickness of 150 nm indicated a significant photocatalytic activity in visible light with 22% higher efficiency in comparison with undoped TiO2 film. Development of TiO2 based photocatalytic thin films by a simple method of airbrushing, builds up the hope for industrial scale applications in future.

• 出版日期2015-12-1