Fabrication and characterization of FeRh nanoparticles

The magnetic and structural properties of FexRh100−x (x=35–80) nanoparticles fabricated by a solution phase chemical method have been studied systematically. From x-ray diffraction results, as-deposited nanoparticles of FeRh reveal a chemically disordered fcc structure which can be transformed into CsCl-type structure through thermal annealing. The high-resolution transmission electron microscopy observations of FeRh nanoparticles indicate that the average size of 3–5nm in as-deposited state and larger size (10–15nm) particles are also distributed in the annealed sate. Nanoparticles with x=35–55 exhibit the behaviors of magnetization with temperature, which suggests the transition from the AFM to FM phases at around 100–200°C, whereas those with x=80 do very little change of magnetization with temperature. It is also found that there seems an effect of applied magnetic field on transition, that is, the transition temperature is shifted to a lower side upon the application of magnetic field during the transition process.