Structure, morphology, and magnetic properties of NiFe2O4 powder prepared by molten salt method.

A series of soft magnetic nickel ferrite (NiFe 2 O 4) samples were successfully synthesised at 1000 °C over a period of 2 h through the molten salt synthesis method using iron oxide red as iron-bearing raw materials. After the cubic spinel structured NiFe 2 O 4 was prepared, the lattice parameter, oxygen positional parameter, M (Fe, Ni)-O bond length, and distribution of cations at tetrahedral and octahedral sites were determined using XRD. The fitting results of Raman spectroscopy demonstrated that the cations of Fe and Ni constituted complex compounds (MO 4) at the tetrahedral site. The morphologies of the synthesised NiFe 2 O 4 samples displayed different shapes and sizes when different molten salts were used as the medium. In addition, energy dispersive spectroscopy was used to analyse the composition of the samples, which indicated the samples were composed of Ni, Fe, and O. The highest value of saturation magnetisation (44 emu/g) was obtained with the NaCl-Na 2 SO 4 molten salts. Unlabelled Image • NiFe 2 O 4 were successfully synthesised by the molten salts method with different eutectic molten salts as intermediate medium. • The cations distribution of prepared NiFe 2 O 4 at tetrahedral and octahedral sites have been obtained from XRD. • The highest value of the saturation magnetization (44 emu/g) was obtained with NaCl-Na 2 SO 4 molten salts. [ABSTRACT FROM AUTHOR]