Abstract
We synthesized polycrystalline materials of a double perovskite system Sr2Fe(Ru1-xWx)O6 with x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0. These materials were made by the solid-state-reaction method, in three types of atmospheres: as-grown in air, annealed in O2, and annealed in Ar-H2 (Ar with 1% H2). From X-ray diffraction and the Mössbauer effect, we found that the samples of Sr2FeRuO6 became single-phase after annealing in O2. On the other hand, single-phase Sr2FeWO6 was obtained after annealing in Ar-H2(Ar with 1% H2).
The lattice constants showed a monotonic increase from x = 0.0 to 0.8, and Fe had a trivalent state in this region.
