The effect of neodymium substitution on the structural and magnetic properties of nickel ferrite

Abstract Nickel ferrite NiFe 2 O 4 is a typical soft magnetic ferrite with high electrical resistivity used as high frequency magnetic material. Neodymium (Nd 3+ ) doped NiFe 2 O 4 materials were fabricated using solid state reaction. The properties of the obtained material were investigated by X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM), Fourier-Transform Infrared Spectroscopy (FT-IR), magnetic measurements on SQUID and Mossbauer spectroscopy. It was found that the material consists of two different phases: Nd 3+ doped NiFe 2 O 4 and NdFeO 3 . The Nd 3+ ions occupy cation sites of the NiFe 2 O 4 inverse spinel structure. NdFeO 3 phase occurred when the level of Nd 3+ atoms exceed a percolation limit. The presence of both phases was confirmed by SEM observations. The Mossbauer spectra analysis showed two sextets, which can be ascribed to iron atoms in tetrahedral and octahedral positions. From their intensities it is concluded that Nd 3+ occupies octahedral sites in the spinel structure of NiFe 2 O 4 , which were originally occupied by Ni 2+ .