Influence of Zn substitution on structural, microstructural and dielectric properties of nanocrystalline nickel ferrites

Nanosized nickel–zinc ferrites having the chemical formula Ni(1−x)ZnxFe2O4 for 0 ≤ x ≤ 1 were synthesized by citrate precursor method. The synthesized nanopowder was densified at a temperature 850 °C. XRD diffraction results confirm the spinel structure for the prepared compounds. Lattice parameter decreases from 8.490 to 8.337 Å with increase in the Zn content. The average particle size identified by HRTEM was ∼45 nm and indicates nanocrystalline nature of the compounds. The Zn content has a significant influence on the dielectric properties of as sintered samples, such as dielectric constant, dielectric loss tangent and dc resistivity. These values decrease with increasing zinc content.