Effect of ammonolysis time on magnetic and transport properties of Sr2FeMoO6 compound

The result of Fullprof_suite refinement shows that the structure of Sr2FeMo(O1−xNx)6 is assigned to tetragonal system with space group I4/mmm and their cell parameters are decreased with ammonolysis time. The M−T curve demonstrates that the Curie temperature of each specimen is higher than 300 K and that a magnetic transition temperature appears. The initial magnetic susceptibility obtained from isothermal magnetization curve shows an increase with ammonolysis time at 78 K and room temperature, respectively. Each sample shows a large magnoresistance in a 1.0 T magnetic field. The samples with different ammonolysis time show different electrical transport behavior in studied temperature range. Under a 1.0 T magnetic field the electron–electron and electron−magnon scattering are suppressed for N-doped samples. However, a 1.0 T magnetic field extends electron–electron scattering and suppresses electron–magnon scattering for N-undoped sample. For the samples ammonolyzed time being more than or equal to 8 h demonstrate a characteristic of O–N disorder in the investigated temperature range.

► Cell parameters of Sr2FeMo(O1−x,Nx)6 decrease with ammonolysis time.
► B increases and decreases with ammonolysis time in low- and in high-temperature region, respectively.
► The electrical transport behavior shows disordered system in longer ammonolysis time.