Visible-light photocatalysis in nitrogen-doped titanium oxides

To use solar irradiation or interior Lighting efficiently, we sought a phot ocatalyst with high reactivity under visible Light. Films and powders of Ti O2-XNX have revealed an improvement over titanium dioxide (TiO2) under visi ble Light (wavelength < 500 nanometers) in optical absorption and photocata lytic activity such as photodegradations of methylene blue and gaseous acet aldehyde and hydrophilicity of the film surface, Nitrogen doped into substi tutional sites of TiO2 has proven to be indispensable for band-gap narrowin g and photocatalytic activity, as assessed by first-principles calculations and x-ray photoemission spectroscopy.