Efficient fabrication and photocatalytic properties of TiO2 hollow spheres

Titania hollow spheres were synthesized via the styrene-methyl methacrylate copolymer (PSMMA) spheres as templates in conjunction with the sol-gel method without any surfactant or polyelectrolyte. Uniform TiO2 hollow spheres were made up of loosely aggregated anatase-phase nanoparticles. Compared to TiO2 nanoparticles (NPs), TiO2 hollow spheres exhibited a higher photocatalytic activity for the degradation of methyl orange (MO), which may be attributed to their larger specific surface area, more abundant porous structure and larger band-gap energy. In addition, the hollow spheres catalysts can be recycled. (C) 2008 Elsevier B.V. All rights reserved.