Synthesis of Co-doped Sr-hexaferrites by Sol-gel Auto-combustion and its Electrical Characterization

Co-substituted M-type hexaferrites with general formula SrFe12-xCoxO19 (x = 0.0, 0.4, 0.8, 1.2) have been prepared using sol-gel auto-combustion technique. The crystal structure of the prepared samples was determined using X-ray diffractometrey, which confirmed the characteristic hexagonal phase present in all the samples without any impurity. The diffraction data was utilized to evaluate the lattice parameters, unit cell volume, crystallite size, X-ray density and porosity of the samples. The values of all these parameters were observed to be affected by the substitution of Co at Fe-sites in the samples. Low temperature electrical measurements revealed an increase in resistivity with increase in temperature depicting the semiconducting behavior of the prepared samples.