Efficient Visible-Light Photocatalysts from Sensitized TiO2 Nanospheres

Abstract

Sensitized TiO2 nanospheres with uniform diameter of ca. 100 nm were successfully synthesized by a hydrothermal method using urea as templates and subsequently employed as robust visible-light photocatalysts. The photocatalytic activities of the sensitized TiO2 nanospheres evaluated by photodegrading methyl orange (MO) were recorded, giving the best photocatalytic performance for the sample synthesized at 110°C for 36 h. The photocatalytic mechanisms of the sensitized TiO2 nanospheres were attributed to the reduction of bandgap energies and the sensitizing effect of melon. The resultant melon acted as a sensitizer to absorb visible light and induced electrons which participated in the photodegradation of MO molecules. The new concept was helpful to guide the synthesis of robust photocatalysts, dye-sensitized solar cells, or hybrid solar cells, and the results suggested that the sensitized TiO2 nanospheres were very promising for enhancing the visible-light photocatalytic activity of TiO2 photocatalysts.