Investigation of Temperature Effect on Structural and Magnetic Properties of La-doped Cobalt Ferrites

In the present work, La+3 - substituted Co-ferrites of chemical composition CoLa0.06Fe1.94O4 (x = 0.06) was prepared applying the co-precipitation method and prepared samples was annealed at different temperatures such as 700-1200 °C for 6 h with step interval of 100 °C. The uniqueness of this work is that only x= 0.06 sample to study the effect of cubic spinel microstructure at different annealed temperatures was selected. The prepared samples were characterized by X-ray diffraction (XRD) technique, Scanning electron microscopy (SEM), Energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and VSM. The XRD and FTIR techniques confirm the spinel ferrite structure. The average crystallite size was found 26.5 nm to 106 nm by using Scherer’s formula. When the temperature was increased, average crystallite size also increased. SEM images showed that the size of grain increased with increase of annealing temperature and confirmed the particle size as analysed by XRD. EDX spectra clarified the presence of elements in the samples by showing their respective characteristics peaks of Co, O, La, and as per prepared composition. From M-H loop, the obtained values of Ms = 59.74 emu/g and coercivity ≥ 700 Oe showed that prepared magnetic samples may be applied as magnetic recording media.