Degradation of methylene blue under UV and visible light illumination by yttria doped titania nanoparticles

Yttria doped TiO₂ nanoparticles were prepared by sol-gel method using the non-aqueous solutions in presence of urea and without it followed by calcination at 500–750 °C for 2h. Photocatalytic activity of the samples was determined by degradation methylene blue under Hg and solar light imitating illumination. Specific surface area, crystallite size, phase transition of TiO₂ and photocatalytic activity depend on content of Y₂O₃ and presence of urea during synthesis. The highest photocatalytic activity showed TiO₂ doped with 0.8–1.0 wt.% of yttria.