Crystal chemistry and thermal behavior of [(U0.3Th0.7)1-yNdy]O2+x; 0≤y≤0.4

Synthesis, X-ray, chemical analysis and thermal properties of Nd doped (U, Th)O2 mixed oxides of the formula [(U0.3Th0.7)1-yNdy]O2+x; (Where y ​= ​0–0.4) are reported in this work. The Nd doped mixed (U, Th)O2 oxides were synthesized using gel combustion method followed by heating the precursors at 1673 ​K in reduced atmosphere. Powder X-ray Diffraction (XRD) patterns of the mixed oxides showed retention of a single FCC phase up to 40 ​mol% Nd. In order to show a relationship between lattice parameter of FCC phase with the concentrations of the dopant and oxygen non–stoichiometry, reduced mixed oxides were further heated in different atmospheres up to 1673 ​K. The relations between lattice parameter (a0) with oxygen non–stoichiometry (x) and dopant content (y) are expressed as: a0 (Ǻ) ​= ​5.5580–0.112 x - 0.154 ​y for x ​> ​0; 0≤ y ​≤ ​0.2. a0 (Ǻ) ​= ​5.5580–0.300 x - 0.130 ​y for x ​