Nanocomposite TiO2-ZnO for Dyes Photocatalytic Degradation

The most progressive and promising way to increase the photocatalytic activity of Titanium (IV) oxide is the creation of its composites with other semiconductors. In the presented article, TiO2-ZnO nanocomposite was synthesized by zinc (II) oxide nanoparticles deposition on the surface of the Evonik AEROXIDE® TiO2 P25 industrial photocatalyst. The phase composition, nanoparticles size, and optical band gap of the synthesized nanocomposite were determined. Lattice constants and Crystallites size were calculated. TiO2-ZnO nanocomposite showed extraordinarily high photocatalytic activity toward the anionic dye of Congo red and less activity toward methyl blue and methyl green cationic dyes. This difference in the properties of the nanocomposite was explained by the high content of weakly basic Bronsted surface centers, which were hydroxyl groups attached to the edge regions of the photocatalyst surface, as well as directly to ZnO and TiO2 nanoparticles.