  The preparation of BaCeO3 doped by yttrium and indium oxides
(BaCe0.6Y0.3In0.1O2.8) has been performed by solid-state reaction from BaCO3,
CeO2, Y2O3, In2O3. The compound BaCe0.6Y0.3In0.1O2.8 has been synthesized for
the first time. The X-ray measurements have showed that BaCe0.6Y0.3In0.1O2.8
has an orthorhombic structure (space group Pmcn). The standard formation
enthalpies of BaCe0.6Y0.3In0.1O2.8 have been determined by solution calorimetry
combining the solution enthalpies of BaCe0.6Y0.3In0.1O2.8 and BaCl2 + 0.6CeCl3
+ 0.3YCl3 + 0.1InCl3 mixtures in 1 M HCl with 0.1 M KI at 298.15 K and
literature data. It has been obtained that above-mentioned mixed oxide is
thermodynamically stable with respect to their decomposition into binary oxides
at room temperatures. It has been also shown that BaCe0.6Y0.3In0.1O2.8 has been
more thermodynamically favored than BaCe0.9In0.1O2.95.
