Sub-solidus phase equilibria in CeO2-SrO system

In this communication, we report on the synthesis and characterization of a series of compounds with the general composition Ce1-xSrxO2-x (0.0 less than or equal to x less than or equal to 1.0), to establish a detailed phase relation in the CeO2-SrO system. The X-ray diffraction (XRD) pattern of the each product was refined to determine the solid solubility and the homogeneity range. The solid solubility limit of SrO in CeO2 lattice, under the slow cooled conditions, is represented as Ce0.91Sr0.09O1.91 (i.e. 9 mol% of SrO). A careful delineation of the phase boundary revealed that the stoichiometric SrCeO3, in fact, contains a little amount of CeO2 also. The mono-phasic compound could be obtained at the nominal composition Sr0.55Ce0.45O1.45. The nominal composition Sr2CeO4, under the heat treatment used in the present investigation, was a bi-phasic mixture of SrCeO3 and SrO. No new ordered phases were obtained in this system. (C) 2002 Elsevier Science B.V. All rights reserved.