Magnetic properties of Gd2O3 doped UO2 nanoparticles

TOBIA, DINA; SOLDATI, ANALIA L.; FERNANDEZ ZUVICH, AFRA; GANA WATKINS, IGNACIO; MILANO, JULIAN; WINKLER, ELIN

Bariloche

Simposio; XXIII Latin American Symposium on Solid State Physics; 2018

The study of lanthanides and actinides oxideshas attracted a lot of interest in the scientific community as they presentcomplex electronic structures due to the interaction between the spin and thedifferent orbital degrees of freedom, conferring these materials unusual andvaried properties. Recently, much of the attention was focused on theproduction and study of actinides nanoparticles (NPs), specially regarding theuranium species, due to their potential applications in the nuclear energyproduction. Gd is usually incorporated into the UO2 nuclear fuel as a burnablepoison, because of its high cross section for neutron absorption. However, thefabrication process of the solid solution (U, Gd)O2 and the amount of Gdincorporated could affect some physical and chemical properties, that caneventually alter the proper and safe performance of this fuel in reactors, aswell as the stability in storage and disposal conditions.UO2 nanoparticles doped with 4, 8, 10 and 15wt% Gd2O3 were synthesized by the ?Reverse Strike? co-precipitation method. Athorough study of the structural and chemical homogeneity properties wasrecently conducted [1], indicating that the nanoparticles have homogenouscomposition at the micrometer scale. In this work we present a study of themagnetic properties through magnetization and electron paramagnetic resonancespectroscopy (EPR) experiments. Particularly, EPR spectroscopy allows to obtainmicroscopic information of the crystalline environment and spin-latticerelaxation that complements the magnetic and structural characterization. The studiessignal the presence of different magnetic interacting mechanisms, depending onGd concentration. We discuss the influence of the synthesis route, grain sizeand Gd concentration on the obtained results.