Solubility of Ce4+ and Sr2+ in the pyrochlore lattice of Gd2Zr2O7 for simulation of Pu and alkaline earth metal

Abstract The solubility of Ce 4+ and Sr 2+ has been studied for the simulation of plutonium, and alkaline-earth metal elements, which are the common fission products in a nuclear fuel, in the zirconate pyrochlore lattice of Gd 2 Zr 2 O 7 by the A site substitution. A number of compositions with general stoichiometry Gd 2− x Sr x Zr 2 O 7− x /2 and Gd 2− x Sr x /2 Ce x /2 Zr 2 O 7 have been synthesized and characterized by powder XRD. From the XRD data, the solubility of Sr 2+ is estimated to be about 1.25 mol%. Further addition of Sr 2+ leads the separation of SrZrO 3 perovskite phase. The solubility of Sr 2+ increases to 2.5 mol% when substituted in combination with Ce 4+ . The solubility of Ce 4+ is estimated to be about 12.5 mol% in the pyrochlore lattice of Gd 2 Zr 2 O 7 . Further addition of Ce 4+ into the pyrochlore lattice leads to the formation of fluorite phase.