Structural and Electrical Properties of Ni-Co Nanoferrites Prepared by Co-precipitation Route.

series of NiCoFeO ( x=0.1, 0.2, 0.3, 0.4, 0.5) spinel ferrites have been synthesized successfully using the chemical co-precipitation route. The materials were characterized by X-rays powder diffractometry (XRD) and the electrical properties. The obtained crystallite size variation was within 15 to 33 nm using the Scherrer formula. The dc electrical resistivity was measured as a function of temperature. It is noticed that σ increases with a rise in temperature. The dielectric measurements were carried out at room temperature as a function of frequency and composition ( x). The dielectric constant ( ε′) and dielectric loss tangent (tan δ) showed a decreasing trend with increasing field frequency. The ac electrical conductivity is calculated from the dielectric measurements; it increases with the rise in frequency. [ABSTRACT FROM AUTHOR]