Synthesis and magnetic properties of core-shell structured (NiCo)O (AFM)/NiCo(FM) magnetic nanoparticles

Summary form only given. The authors report the synthesis, morphology and magnetic properties of (NiCo)O/NiCo AFM-FM nanoparticles. NiCo particles that exhibit a Co-rich core structure were synthesized by co-reduction from Co and Ni metal salts in ethylene glycol. The particle size and surface morphology were evaluated. The surface of the particle was oxidized at 573 K for 4 hours in a controlled atmosphere and an oxide layer about 20 nm thick was developed, creating an exchanged biased core-shell structure. The saturation magnetization, coercivity and hysteresis loop shifts of particles of varying composition and preparation conditions were measured.