Preparation and stability of a new compound SrCe0.9Lu0.1O2.95

Abstract The preparation of SrCeO 3 doped by lutetium oxide (SrCe 0.9 Lu 0.1 O 2.95 ) has been carried out by the solid-state reaction of SrCO 3 , CeO 2 and Lu 2 O 3 . The X-ray measurements have shown that SrCe 0.9 Lu 0.1 O 2.95 has an orthorhombic structure (space group Рnma ). For the first time the standard molar enthalpy of SrCe 0.9 Lu 0.1 O 2.95 formation has been determined by solution calorimetry in combination with standard molar dissolution enthalpies of SrCe 0.9 Lu 0.1 O 2.95 and SrCl 2  + 0.9CeCl 3  + 0.1LuCl 3 mixture in 1 M HCl with 0.1 M KI at 298.15 K and other thermochemical data. It has been found out that the mixed oxide mentioned above is thermodynamically more stable than the component oxides at room temperature. It has been also shown that SrCe 0.9 Lu 0.1 O 2.95 is thermodynamically more favored than 0.9SrCeO 3  + 0.1SrO + 0.05Lu 2 O 3 mixture. We have established that Lu adding increases SrCeO 3 thermodynamic stability.