Preparation of BaCe1−xYxO3−δ single phase by liquid phase mixing method and its structural variation on Y content

As a preparation method of proton conducting BaCe1−xYxO3−δ, solid state reaction method and liquid phase mixing one from same raw materials have been compared. By solid state reaction of BaCO3, CeO2 and Y2O3, segregation of Y2O3 was observed in the specimens with x larger than 0.15. Employing liquid phase mixing method, BaCe1–xYxO3–δ single phase of 0.00 ≤ x ≤ 0.25 with homogeneous Y distribution, has been successfully prepared. It was revealed that crystal system of BaCe1−xYxO3−δ was orthorhombic distorted perovskite and monoclinic distorted one for 0.00 ≤ x ≤ 0.10 and 0.15 ≤ x ≤ 0.25, respectively. The abrupt increase of volume due to the structural phase transition was observed at x between 0.10 and 0.15.