Cobalt plays a crucial role in the systematic understanding of magnetic phenomena originating from 3d transition metals. Particularly, recent studies of Co systems doped with nitrogen (Co–N) have attracted a lot of attention for applications in spintronics and high-density magnetic data-storage devices. In this work, in order to understand the effect of interstitial incorporation of N atoms into a face-center cubic (fcc) Co lattice, we have studied the structure, elastic, and magnetic properties of spherical-like bulk CoNx (x = 0.06–0.07) samples. These samples were synthesized through a high-pressure solid-state metathesis reaction. We demonstrate that the use of a certain concentration of interstitial N atoms tends to stabilize the lattice of fcc Co at ambient conditions. Such a stabilizing effect is found to originate from the covalent bond between Co atoms and N atoms. High-pressure synchrotron x-ray diffraction indicates that the incorporation of N atoms into fcc Co has little effect on the elastic property up to 27.2 GPa with a bulk modulus (B0) of 200 GPa; the latter is found to be comparable to that of fcc and hcp Co. CoNx samples exhibited ferromagnetic behavior with saturation magnetization up to 153.55 emu/g and coercivity of 16.25 Oe. The introduction of small amounts of nitrogen in the cobalt matrix was found to induce a significant decrease in the coercive force parameter.
The effect of interstitial-site nitrogen on structural, elastic, and magnetic properties of face-center cubic Co
Binbin Wu, Feng Zhang, Qiwei Hu, Qiqi Tang, Shan Liu, Xiaojun Xiang, Yuanhua Xia, Leiming Fang, Hiroaki Ohfuji, Tetsuo Irifune, Li Lei; The effect of interstitial-site nitrogen on structural, elastic, and magnetic properties of face-center cubic Co. J. Appl. Phys. 14 March 2021; 129 (10): 105901. https://doi.org/10.1063/5.0037917
Download citation file: