Synthesis, characterization and photocatalytic activity of PdO/TiO2 and Pd/TiO2 nanocomposites

Sol-gel, sol-gel-hydrothermal and photodeposition methods were used to synthesize pure TiO2, PdO/TiO2 and Pd/TiO2 nanostructures. Citric acid was used as a stabilizer, reducing and capping agent, since it is green, available, clean and nontoxic. During the one of the steps, stearic acid was used as an organic solvent to obtaining homogenized sol. In the following, Pd/TiO2 nanostructures were synthesized by photodeposition in 0.1, 0.5 and 1 wt% Pd on the surface of P25 nanoparticles under ultraviolet (UV) irradiation. Product characterization was performed by X-ray diffraction, scanning electron microscopy, energy-dispersive spectroscopy and diffuse reflectance spectroscopy. The photocatalytic behaviors of pure TiO2, PdO/TiO2 and Pd/TiO2 nanocomposites were evaluated using the degradation of a Rhodamine B aqueous solution under UV light irradiation. Among them, excellent performance for Pd/TiO2 nanocomposite containing just 1 % palladium in photocatalytic dye degradation was observed and only after 20 min, 88 % of dye was degraded.