Photo-catalysis activity of TiO2, Co3O4, Co3O4 @TiO2, and TiO2@Co3O4 nanoparticles prepared by pulsed-laser ablation

Water pollution is practically one of the most challenging subjects. Photo-catalysis using nanoparticles is one of the effective techniques that are employed for organic material removal. In this work we explore the optical characteristics and the photo-catalytic activity of Co3O4, TiO2, Co3O4@TiO2, and TiO2@Co3O4 nanoparticles prepared by pulsed laser ablation. Effective dye removal has been obtained by using these nanoparticles. Although the prepared nanoparticles exhibit different optical properties, they show close photocatalytic activities. As single material, the dye removal activity of Co3O4 and TiO2 is nearly terminated after a while. However, by forming core@shell structures of these nanoparticles an effective and continuous dye removal process has been obtained.