SYNTHESIS AND CHARACTERIZATION OF COBALT SUBSTITUTED W TYPE HEXAGONAL FERRITES

In this work W type hexagonal ferrites with chemical composition Sr1-xCrxCo2Fe16O27(x= 0.0, 0.02, 0.04, 0.06, 0.08, 0.1) were synthesized by sol gel auto combustion method. Annealing of the samples was done at 1200 C for 8 hours. Structural and optical properties and grain morphology of the synthesized samples were studies through X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Ultraviolet visible spectroscopy techniques and scanning electron microscope (SEM). XRD analysis confirmed that all samples exhibited hexagonal W-type single phase crystalline structure at temperature range of 1200oC with no impurity phase. The estimated grain size from SEM images is in the range of 76-139 nm that confirms nanocrystalline structure of samples with hexagonal structure. The FT-IR spectral analysis exhibited that absorption band occurred in ranging from 450 cm-1 to 650 cm-1 . Evidence of successful formation of hexaferrites was revealed by FTIR spectra of prepared samples. The existence of metal oxygen bond at octahedral site and tetrahedral site confirms that all fabricated samples exhibit W-type hexagonal ferrites. Optical characteristic of Sr1-xCrxCo2Fe16O27 analyzed by UV-Visible spectroscopy. The absorption spectra of synthesized nanoparticles of W-type recorded in range of wavelength 300 to 800 nm. This spectroscopy is significant in exploration of materials electronic properties. W-type hexagonal ferrites are suitable for high frequency application such as microwave devices.