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.

Stabilization of anatase phase in the rare earth; Eu and Sm ion doped nanoparticle TiO2

“…The RE ion doped nanoparticles were synthesized with the same method mentioned above [10], except for the addition of the corresponding RE dopant solution into the hydrolyser solution. The dopant solutions were prepared by dissolving RE chloride hydrates (EuCl 3 ·6H 2 O, SmCl 3 ·6H 2 O, 99.9%, Kojundo Chemical, Tokyo) in DI water.…”

“…The average crystallite size for TiO 2 with various doping concentrations of Eu and Sm, sintered at 900 • C are given together with the nanoparticle size obtained from AFM[10] for the Sm doped one sintered at 950 • C. The mass fraction of anatase phase for RE doped TiO 2 films sintered at 900 • C shows that the domination of anatase phase is obtained at the same time with the abrupt reduction of crystallite size.…”

Studies on Thermal Migration of Eu Ion Doped into TiO2 Nanoparticles

“…The interest towards TiO 2 nanoparticles is also based on the fact that they can be applied as a photocatalytic material. Recent studies on Eu-doped TiO 2 nanoparticles [20][21][22][23][24][25] have reported that Eu doping particularly enhances the photocatalytic activity of TiO 2 in decomposing organic compounds. Additionally, our previous research showed that Eu ions effectively suppressed the growth of nanoparticles and stabilized the anatase phase, 26) which was advantageous for photocatalytic application.…”