In situ surface hydrogenation synthesis of Ti3+ self-doped TiO2 with enhanced visible light photoactivity.

A novel one-step, vapor-fed aerosol flame synthetic process (VAFS) has been developed to prepare Ti(3+) self-doped titanium dioxide (TiO2). The freshly formed TiO2 was in situ surface hydrogenated during the condensation stage by introducing H2 above the flame, and Ti(3+) ions were created near the surface of TiO2. The relative content of Ti(3+) ions near the surface of TiO2 is estimated to be 8%. Because of the high absorption of visible light and suppression of charge recombination, the photocurrent density and decomposition of MB under visible light irradiation were remarkably enhanced. This study demonstrates a simple, potential method to produce Ti(3+) self-doped TiO2 with effective photoactivity in visible light.