Photocatalytic properties of TiO2 nanotubes doped with Ag, Au and Pt or covered by Ag, Au and Pt nanodots

Titania nanotube arrays have been prepared by anodic oxidation of titanium foils in an electrolyte solution containing a mixture of hydrofluoric acid, ethylene glycol, and phosphoric acid. The initially amorphous nanotubes were found to crystalize in an anatase phase upon thermal treatment at 500°C. Anatase crystalline phase showed a significant improvement in the photocatalytic properties of the prepared samples, which was evaluated by studying their efficiency towards Rhodamine B dye degradation. Additionally, the effect of doping titania nanotubes with noble metals (e.g. Ag, Pt, and Au), or covering their surface with noble metal nanoparticles, was studied regarding their capabilities towards the photocatalytic degradation of Rhodamine B dye. A positive effect when samples were doped with Ag was revealed.