Radiation effects, photoluminescence and radioluminescence of Eu-doped (Y0.7Gd0.3)2O3 nanoparticles with various sizes

(Y(1-x)Ln(x))(2)O-3 oxides (Ln = Y, Gd, Lu) doped with Eu-3(+) ions are widely used as commercialized scintillators in medical and industrial scanning applications, with high performance and attractive properties. In this work, effects of high-energy radiation on luminescence properties of (Y1-xGdx)(2)O-3: Eu3+ powders with different particle sizes in the nanometric range are analyzed. Powders were prepared by polymer complex solution route, followed by annealing. Nanoparticles were obtained with an average size between 20 and 120 nm according to annealing conditions (time and temperature). Samples were exposed to gamma-irradiation (doses up to 4 MGy) on a commercial gamma-irradiation plant. The effect of irradiation on different nanoparticle size is followed by XRD, TEM and monitoring their luminescence properties. No change was observed in structure, morphology and steady-state emission. On the opposite after irradiation, excited-state lifetimes and quantum efficiency values are particle size dependent.