The Influence of the Au Nanoparticles Dimension on the Photocatalytic Performances of TiO2-Au Porous Composites.

The influence of Au nanoparticles dimension on the photocatalytic performances of the TiO₂ aerogels-Au composites was evaluated. Structural and morphological peculiarities of the TiO₂ aerogel, unloaded and loaded with 5 and ₂₂ nm Au nanoparticles, were studied by transmission electron microscopy technique, X-ray diffraction and N₂-sorption measurements. UV-Vis diffuse reflectance measurements were performed to determine the band gap energies. The photocatalytic activity was evaluated by monitoring the salicylic acid photodegradation. It was found that the Au nanoparticles promote the anatase phase crystallization and produce the decrease of the specific surface area and band gap energy values. The porous composite with the smallest Au nanoparticles dimension exhibits the best photocatalytic performances. [ABSTRACT FROM AUTHOR]