University of Babylon, College of Science for Women, Department of Laser

Physics, Hilla-Najaf Street, Babylon, 51002, Iraq

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 photo- catalytic 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.