Gram-scale wet chemical synthesis of Ag2O/TiO2 aggregated sphere heterostructure with high photocatalytic activity

Ag2O/TiO2 aggregated sphere heterostructure with high photocatalytic activity under the simulated sunlight was achieved via a simple and gram-scale three-step wet chemical synthesis. The Ag2O nanoparticles with a diameter of 10-60 nm were uniformly coated on the surface of the TiO2 aggregated spheres with a diameter of 370-450 nm. Compared with pristine TiO2 aggregated spheres and pure Ag2O nanoparticles, the heterostructure photocatalysts exhibit an enhanced photocatalytic activity under the simulated sunlight irradiation in the degradation of methyl orange. A mechanism was proposed to account for the photocatalytic activity of the Ag2O/TiO2 heterostructure. This report presents that large band gap semiconductor photocatalysts modified by narrow band gap metal oxide will be an effective way to enhance sunlight photocatalytic activity. (c) 2012 Elsevier B.V. All rights reserved.