Influence of neodymium ions on photocatalytic activity of TiO2 synthesized by sol-gel and precipitation methods

Titanium dioxide with and without the addition of neodymium ions was prepared using sol-gel and precipitation methods. The resulting catalysts were characterized by thermal analysis, X-ray diffraction and BET specific surface area. Neodymium addition exerted a remarkable influence on the phase transition temperature and the surface properties of the TiO2 matrix. TiO2 samples synthesized by precipitation exhibit an exothermic event related from the amorphous to anatase phase transition at 510 degrees C, whereas in Nd-doped TiO2 this transition occurred at 527 degrees C. A similar effect was observed in samples obtained using sol-gel method. The photocatalytic reactivity of the catalysts was evaluated by photodegradation of Remazol Black B (RB) under ultraviolet irradiation. Nd-doped TiO2 showed enhanced photodegradation ability compared to undoped TiO2 samples, independent of the method of synthesis. In samples obtained by sol-gel, RB decoloration was enhanced by 16% for TiO2 doped with 0.5% neodymium ions. (C) 2010 Elsevier B.V. All rights reserved.