Bulk and lattice thermal expansion in Ce 1− xSr xO 2− x (0.0≤ x≤0.10)

Abstract

In this communication, we report on the bulk and lattice thermal expansion studies on a number of compounds, within the homogeneity range of solid solutions, in a series with the general composition Ce 1− x Sr x O 2− x (0.0≤ x≤0.10). The XRD pattern of each product was refined to determine the solid solubility of SrO into the lattice of CeO 2, and the homogeneity range. The composition with maximum solid solubility limit of SrO in CeO 2 lattice, under the slow cooled conditions, was delineated as Ce 0.91Sr 0.09O 1.91 (i.e. 9 mol.% of SrO). The bulk thermal expansion measurements from ambient to 1123 K, as investigated by a dilatometer, revealed that the α l (293 to 1123 K) values for the compositions within the homogeneity range increase from 11.58×10 −6 to 12.13×10 −6 K −1 on increasing the Sr 2+ content from 0 mol.% (i.e. CeO 2) to 9 mol.%, i.e. the upper solubility limit of SrO into the lattice of CeO 2. A similar trend was observed in the lattice thermal expansion coefficients α a (293 to 1473 K) as obtained by a high temperature-XRD.