Photocatalytic oxidation of 2-propanol under visible light irradiation on TiO_2 thin films prepared by an RF magnetron sputtering deposition method

摘要

Visible light-responsive TiO_2 (Vis-TiO_2) thin films able to absorb UV and visible light in wavelength regions of 250-600 nm were successfully developed by applying a radio-frequency magnetron sputtering deposition method. These Vis-TiO_2 thin films exhibited high activity for the photocatalytic oxidation of 2-propanol diluted in water even under visible light irradiation (λ≥450 nm). The photocatalytic activity of Vis-TiO_2 thin films was dramatically enhanced by the deposition of Pt particles on the surface. Secondary ion mass spectrometry measurements revealed that Pt particles are distributed from the top surface to the deep bulk of Vis-TiO_2 thin films with a columnar structure. The unique columnar structure of Vis-TiO_2 thin films plays an important role in the high photocatalytic performance.