IMPACTS OF SUBSTITUTING Ni2+ IONS ON STRUCTURAL AND ELECTRICAL PROPERTIES OF W-TYPE BARIUM BASED HEXAFERRITES

W-type Barium based ferrites with composition BaZn2-xNixFe16O27 for (x = 0.0, 0.1, 0.2, 0.3, 0.4) were synthesized by chemical co-precipitation technique by 8h sintering at 1100 degrees C in order to investigate their structural and electrical properties. XRD patterns confirmed the formation of w type phase. It was observed that, initially the crystallite size increased from 15.285 nm to 16.056 nm with increasing concentration of nickel up to x = 0.1 but then gradually decreased to 15.68 nm up to x = 0.4. This decrease showed that nickel act as crystallite inhibitor. Lattice constants decrease with increasing concentrations of substituted ions attributed to the fact that ionic radius of nickel (0.069 nm) is less than that of zinc (0.072 nm). X-ray density increased from 2.43 to 2.50g/cm(3) with increase in nickel concentration up to x = 0.3 and then decrease to 2.47g/cm(3). As the atomic weight of nickel (58.69 amu) is smaller than zinc (65.37 amu). So the X-ray density should decrease with increasing nickel contents but here increase contradicted which may be due to variations in lattice distortions. FTIR spectra showed three frequency bands corresponding to tetrahedral, N-O stretching vibration of NO3 ions, stretching and twisting of -OH surface hydroxy group respectively. Resistivity increased with increase in nickel concentration from 0.59x10(7) Omega cm to 5.45x10(7) Omega cm.