Rare Earth Ion-doped Tio <sub> 2 </ Sub> Photocatalyst

With the rapid development of nanotechnology, nanometer TiO₂ has expressed the outstanding properties on conversion and storing of solar energy, sewage treatment, air purification, degerming kept clean, self-cleaning antifogging, and become one of the major investigations in the field of nanomaterials application, In this paper, on theadoption of the modification of nano-TiO₂ photocatalyst by rare earth ions doping, the following aspects were studied.1) TiO₂ nanocrystals were obtained via sol-gel method and the grain sizes were less than 10nm. The main factors, the crystal phase, grain size and surface morphology, which influenced photocatalytic properties, were studied by characterizing the samples. The processing parameters of TiO₂ nanocrystals were investigated. The best molar ratio of Ti(OBu)₄: ethanol: HC1: H₂O was 1:20: 1: 0.1. The best calcination temperature was 450°C and the best holding time was 0.5 h.2) Rare earth ion-doped (La³⁺,Y³⁺, Eu³⁺) TiO₂ nano-crystals were obtained. The research results showed that the photocatalytic properties of rare earth ion-doped TiO₂ could be improved obviously with the doping of rare earth ions and different doping ions had different optimum value. Also, the photocatalyst had much high degradation ratio under sunlight. The degradation ratio of La-doped TiO₂ nano-crystals for paper-making black liquid was increased 37% than that of the pure TiO₂.3) The photo-catalytic properties of TiO₂ nano-crystals co-doped with two kinds of rare earth ions were investigated. It was found that their photo-catalytic properties enhanced greatly, especially was that co-doped with La³⁺ and Y³⁺ ions. The degradation ratio for 1h was increased from 34.1.9% to 65.10%, and the degradation ratio for 2h was increased from 37.54% to 96.40%.4) The photo-catalytic activities of TiO₂ nanocrystals prepared by the addition of ethylenediamine was much higher than those prepared by the addition of HC1, whether were under violent light or visible light. The photodegradation efficiency was increased 30%.In a word, many significative results including preparation methods (nanocrystal,...