Synthesis and Properties of Fe-Ni Nanoparticles

In this work, we report a simple method to prepare the Fe-Ni alloy nanoparticles by reducing NiFe2O4 spinel ferrite nanoparticles at 600 °C in a hydrogen atmosphere. Structural analyses of the Fe-Ni alloy by XRD diffraction showed that the alloy sample is a complete single phase after the deoxidizing time of 12 hours. Field effect scanning electron microscopy (FESEM) images showed microstructure with particle sizes at the nanometer scale. The valence state of the iron ion was determined from X-ray absorption near edge spectroscopy (XANES), showing that the sample had completely Feº. Magnetic curves of Fe-Ni alloy nanoparticles were studied by vibrating sample magnetometer (VSM) at temperatures from 88 K to 900 K from that the technical saturation magnetization Ms and magnetic order temperature TC were determined. The magnetoresistance effect MR of Fe-Ni alloy nanoparticles was also studied which is related to the tunneling of conduction electrons via grain boundaries. The obtained results of the work proved that this synthesis method is a facile, effective, and low-cost route that can be used to prepare Fe-Ni alloy nanoparticles. 
 