Abstract:
There has been a tremendous interest in hexagonal ferrites during the last ten years for a number of marvelous applications. “Due to their expanded use, hexaferrites has become very important magnetic material being commercially produced. Strontium based M-type hexaferrites, SrM, (SrFe12O19) is one of such materials that is currently used in these applications. In the current work cobalt dopant substitution is performed in series of Sr (1-x) CoxFe12O19 (x = 0, 0.2, 0.35, 0.5) using sol gel method. The aqueous solution, containing metal nitrates were brought in use to prepare strontium hexaferrite nanoparticles. Thepprepareddsampleswwereccalcined att1050 °C for88 hrs. Thessynthesized samples were characterized using X-ray diffraction (XRD), Scanning Electron Microscopy (SEM) and Fourier Transform Infrared spectroscopy (FTIR). Impedance analyzer and LCR meter was used for performing dielectric measurements. The formation of hexagonal Sr(1-x)CoxFe12O19 was confirmed using (XRD). Debye Scherer equation was used to find out the crystallite size that was in range of 37nm – 57nm. The band positions were studied using (FTIR). The study of dielectric properties with change in frequency was done at room temperature. For the cobalt doped strontium hexaferrite Sr(1-x)CoxFe12O19 the real part of dielectric constant enhanced to 77.4 at 250 Hz for x=0.5. The values of dielectric loss for cobalt doped has increased from 2.21to 54.0 at 250 Hz. AC conductivity values also showed increase in cobalt. AC conductivity results explain that electron hopping governs the conduction process. Two probe method is used to measure the resistivity the decrease in resistivity with increase in temperature should enhance conductivity. The electrical properties and conductivity rises with increasing concentration of cobalt. The enhanced dielectric properties and increase in conductivity of the prepared nano particles make it applicable in field of super capacitors and charge storage devices.
