Design and fabrication of a TiO2/nano-silicon composite visible light photocatalyst

Nano-silicon (nc-Si) was utilized as the charges generator to promote the photocatalytic and super-hydrophilic reactivity of TiO2 film under visible light irradiation. The photocatalytic ability of TiO2/nc-Si composite photocatalyst was evaluated by a set of experiments to photodecompose 100 ppm methylene blue (MB) in aqueous solution. And the super-hydrophilic property was characterized by measuring the water droplet contacts angle, under visible light irradiation in atmospheric air and at room temperature. Under 100 mW/cm(2) visible light irradiation, the droplet contact angles were reduced to 0 degrees within 4 h with nc-Si charge generator. Additionally, the rate constant of MB photo-degradation was promoted 6.6 times. (c) 2006 Elsevier B.V. All rights reserved.