Effects of Divalent Ion Substitution on the Microstructure and Magnetic Properties of SrCo2-x (MnZnCa)x/3Fe16O27 Nanoparticles

W-type hexaferrite nanoparticles with a composition of SrCo (2-x) (MnZnCa) Fe-x/3 (16) O (27) (x = 0-0.5) were synthesized by a chemical co-precipitation method. The effect of substitution of Mn, Zn, and Ca cations on the structural and magnetic properties of nanoparticles was characterized by X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX), and vibrating sample magnetometer (VSM). The XRD patterns confirmed the existence of hexagonal W-type single phase ferrite. According to the SEM micrographs, it was found that the particle size lies in the range of 40-60 nm, with an irregular configuration. The elemental composition estimated from the EDX analysis was in good agreement with the nominal composition. Hysteresis loops for all samples were measured at a room temperature up to a maximum applied field of 10 kOe. The results revealed that with an increase in substitutional cation contents, the values of saturation magnetization and coercivity decreased from 78.4 to 70.8 emu/g and the values of coercivity also decreases from 1350 to 940 Oe. Correlation between structural and magnetic analyses was also earned out.