2020/12/26 by Mohamed A. Kassem, M. A. Kassem, A. Abu El‐Fadl +7
Chemistry · Energy · Materials Science · Physics and Astronomy · #Analytical Chemistry (journal) #Anisotropy #Chemistry #Coercivity #Condensed matter physics #Crystal structure #Crystallography #Diffraction #Electromagnetic wave absorption materials #Ion #Ionic radius #Iron oxide chemistry and applications #Lattice constant #Magnetic Properties and Synthesis of Ferrites #Magnetic anisotropy #Magnetic field #Magnetization #Materials science #Metallurgy #Mössbauer spectroscopy #Nuclear magnetic resonance #Optics #Physics #Rietveld refinement #Single domain #Spinel #cond-mat.mtrl-sci
paper · pdf · doi:10.1016/j.mseb.2021.115494
23 pages, 7 captioned figures, 6 tables
arxiv created 2020/12/26 · openalex publication_date 2021/10/15 · openalex created_date 2021/10/25 · arxiv updated 2022/03/09 · openalex updated_date 2026/08/05
The effects of Ni2+ substitution on the structure (lattice parameters, cations distribution, average cations radii, cation-cation/anion bond lengths and angles) and the soft magnetic properties of Mg1-xNixFe2O4 (0 ≤ x ≤ 1.0) nanocrystals have been studied by x-ray diffraction with Rietveld refinement, transmittance electron microscopy, Mossbauer spectroscopy and magnetization measurements. The mostly inverse spinel structure was found in MgFe2O4 nanoparticles and the inversion factor is further increased by Ni-substitution up to a complete inversion in NiFe2O4. The synthesized ferrites with a small particle size (20 - 30 nm) exhibit soft magnetic properties of a single-domain behavior with critical domain size about 30 - 40 nm. An observed monotonic increase in magnetization and drastic decrease in coercivity at 5 K by Ni-substitution result in a lowest anisotropy constant Ku (2.8 kJ/m3) for x = 0.5. We discuss the evolution of magnetic properties by Ni-substitution in a correlation with a subsequent cations-redistribution between sites of the two sublattices and corresponding structural changes in the inter-ionic distances.