Structural and magnetic properties of Sr2FeMoO6 film prepared by electrophoresis technique

Double perovskite Sr2FeMoO6 film was fabricated by electrophoresis method on single crystal Si substrate. The post-annealing treatment was carried out at 900 °C, 960 °C, 1060 °C and 1100 °C with 5% H2/Ar atmosphere. Surface micrograph, structural and magnetic properties of the film have been investigated. It is found that the annealing temperature plays an important role on the phase formation and magnetic properties. According to X-ray diffraction (XRD), single phase Sr2FeMoO6 film was obtained at annealing temperature 1100 °C, the film shows typical polycrystal property. However, the superstructure reflection assigning the ordering arrangement of Fe and Mo atoms in the perovskite structure disappears in our XRD pattern. Raman detection finds two peaks at around 440 cm−1 and 620 cm−1, which belongs to Sr2FeMoO6 phase. Consistent with XRD results, typical impurity like SrMoO4 appears at around 880 cm−1 in the film annealed at lower temperature. Microstructure investigation shows that the surface of the film is homogeneous and the grain size of particles increases with annealing temperature. Temperature dependence of magnetization reveal that the highest Curie temperature (TC=282 K) is obtained from the film annealed at 1100 °C. Owing to the large amount of anti-site defect, the highest TC is still lower than that of parent Sr2FeMoO6 powder.