Structural, physical and magnetic evaluations of Ce-Zn substituted SrCo2 W-type hexaferrites prepared via sol gel auto combustion route

Abstract

SrCo2 W-type hexagonal nanoferrites with composition SrCo2-xZnxCeyFe16-yO27 (whereas x = 0, 0.2, 0.4, 0.6, 0.8, 1.0 and y = 0, 0.02, 0.04, 0.06, 0.08, 0.1) were synthesized by sol-gel auto combustion method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM) and Vibrating sample magnetometer (VSM) were used to find out the structural, vibrational, morphological and magnetic properties of SrCo2 W-type hexagonal ferrites. Physical properties such as bulk density (Dbulk), X-ray density (Dxrd) and porosity (%P) of the SrCo2 W type hexagonal ferrites samples were calculated. Bulk density of the samples decreased whereas X-ray density increased with the Ce-Zn substitution in the W-type ferrites. Single phase samples of all the nanoferrites are achieved at the sintering temperature of 1050 °C. Structural parameters such as lattice parameters ‘a’ and ‘c’ were also calculated. Lattice parameter ‘a’ is found to be increased whereas ‘c’ is found to be decreased with the substitutions. Force constants at tetrahedral and octahedral sites are also evaluated which confirm the phase and substitution in W-type hexagonal ferrite. FESEM images showed homogenous and well crystallized at higher substitution of Ce-Zn in SrCo2 W-type hexagonal ferrites. Detailed magnetic parameters such as magnetic remanence coercivity, saturation, Bohr magneton, initial permeability, magneto crystalline anisotropy constant (K) and magnetic field anisotropy (Ha) were measured. Magnetic remanence decreased whereas coercivity, magneto crystalline anisotropy and field anisotropy increased in the SrCo2 W-type hexagonal ferrites samples. The dependence of Hc and Ha on the SrCo2 W-type hexaferrites may be due to the variations in the K and Ms of the substituted samples. Therefore, the prepared SrCo2 W-type nanoferrites with appropriate amount of metal cations are suitable candidate for the microwave devices and high frequency applications.