Development of Eu-Enhanced TiO2 Nanophotocatalyst for Effective Utilization of Spent Nuclear Fuel

Abstract

A UV-photoactive Eu-doped TiO2 nanoparticle activated with its wavelength-matched nanoscintillator is proposed for the effective utilization of spent nuclear fuel. The Eu-doped TiO2 nanoparticles were synthesized by the alkoxide-based sol–gel method at various doping concentrations and sintering temperatures. The X-ray diffraction (XRD) spectra revealed that the existence of the anatase phase of TiO2, which is favorable for photocatalytic application, was extended up to 800 °C by Eu doping. The average crystallite size of 40 nm in the pure TiO2 sintered at 600 °C was decreased by 50% in the case of the 0.5 mol % Eu-doped one. The absorption edge obtained from UV–vis absorbance spectra yielded a slightly blue shift that gave a good agreement with the results of size suppression. The photocatalytic activities of nanoparticles were evaluated from the degradation of methylene blue (MB) solution under UV irradiation, and the optimum activity obtained for the 0.75 mol % Eu-doped TiO2 was three times higher than that of the pure TiO2.