Visible light-assisted photocatalytic oxidation of organic pollutants using nitrogen-doped titania

An experimental research into the aqueous photocatalytic oxidation (PCO) of organic groundwater pollutants, methyl-tert-butyl ether (MTBE), tert-butyl alcohol, phenol, humic substances, 2-ethoxy ethanol and ethylene glycol was undertaken using visible light-sensitive nitrogen-doped titanium dioxide photocatalysts. Nitrogen-doped titania proved to be an effective photocatalyst for MTBE with its action comparable to and even surpassing that of Degussa P25. In contrast, with the other substances the photocatalysts showed negligible activity. This difference was explained by the poor adsorption properties of N-doped catalysts. The predominance of different PCO mechanisms dependent of the surface properties of N-TiO₂ catalysts was elucidated.