Structural and magnetic properties of iron, cobalt and nickel nanoparticles

This study focuses on the synthesis and characterization of iron, cobalt and nickel nanoparticles through sol–gel method and heat-treating technique in argon atmosphere. The structure, morphology and magnetic properties of the as-synthesized products were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM) and superconducting quantum interference device (SQUID) magnetometer. XRD studies indicated that the as-prepared products were iron, cobalt and nickel with well crystallized bcc, fcc and fcc structure, respectively. TEM observations showed that the as-synthesized products composed of spherical shape with size around 2, 2 and 2 nm for iron, cobalt and nickel, respectively. Magnetization results revealed that the as-obtained products showed superparamagnetic character at 300 K. The magnetic anisotropy of the products is much higher than that of bulk owing to the nanostructure.