Photocatalytic activity of titanium dioxide modified with thiourea under the action of visible light

Photocatalyst powders were synthesized from nanosized titanium dioxide crystals modified by sintering with thiourea (TU). The powders contained anatase crystals of various sizes. TU-TiO 2 powders absorbed visible light to produce an oxidizer (oxidizing iodide) and a reducing agent (reducing tetranitromethane). The activity of TU-TiO 2 correlated with the size of nanocrystals. The photocatalytic activity of TU-TiO 2 was suggested to be related to impurity states appearing during modification in the forbidden band of TiO 2 .