Synthesis, characterization and magnetic interactions study of ε-Fe3N-CrN nanorods

The epsilon-Fe3N-CrN composite nanorods are synthesized by wet chemical technique. XRD-Rietveld analysis shows that epsilon-Fe3N and CrN crystallize in the space group P6(3)/mmc and Fm (3) over barm with relative mass compositions 53% and 47%, respectively. The nanorods have an average diameter similar to 30 nm and length similar to 400 nm X-ray photoelectron spectroscopy (XPS) studies show the presence of nitrides and oxynitrides (Fe-O-N/Cr-O-N) at the surface and the presence of elemental Cr in CrN matrix along with the nitrides inside the nanorods, probed by the in-depth profile analysis. The magnetic interactions between the spins of ferromagnetic (FM) epsilon-Fe3N and antiferromagnetic (AF) CrN throughout the volume of the nanorods give rise to exchange bias coupling. The exchange bias phenomenon is influenced by the rough and non-uniform AF-FM interface and spin-glass-like ordering at lower temperatures. The ac susceptibility studies confirm the spin-glass-like ordering.