Structurally related electromagnetic properties of NixFeyO4 nanomaterials synthesized by granulated sodium alginate

Abstract In regard to the synthesis of NixFeyO4 nanoparticles, a new process was presented that used granulated sodium alginate (Na-ALG) prepared by a high-shear wet granulator (HSWG). By using this synthesis route, Na-ALG granules were added directly into metal salt solutions to obtain respective ferrite oxide nanoparticles based on a solid-liquid ion-exchange reaction. The different NixFeyO4 nanopowder samples were verified by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Significant increases in the particle sizes were observed with increased calcination temperatures in this investigation. The structural analysis of NixFeyO4 obtained by XRD Rietveld refinement agreed with the simulated models using the Materials Studio (MS) software. The structural differences of NixFeyO4 due to the increasing Ni2+ concentrations from 0.4 to 1.43 mol were investigated with nominal compositions and confirmed by inductively coupled plasma-atomic emission spectrometry (ICP-AES). The magnetic investigations were carried out using a vibrating sample magnetometer (VSM) and a maximum saturation magnetization (Ms = 37.26 emu/g) was recorded at 20000 Oe with the Ni0.4Fe2.6O4 nanoparticles. All samples showed supermagnetic properties when the Ms values decreased as the Ni2+ concentrations increased. Finally, the synthesized NixFeyO4 samples exhibited excellent discharge-storage capacities even after 200 cycles. This new process not only ensured that the operation was easier to scale up but also much greener since it consumed less than 4% of the water compared with other processes in the literature.