Nanoparticles nickel ferrite of size 6 - 8 nm, synthesized by the coprecipitation method with x varying from 0 to 1.0. The powder samples were characterized by XRD, VSM and FTIR. The average crystallite sizes of the particles were determined from X-ray diffraction. X-ray analysis showed that the samples were cubic spinel. The lattice constant (a o) increased with the increase in zinc substitution. The specific saturation magnetization (M S) of the particles was measured at room temperature. The magnetic parameter of M S, was found to decrease with the increase in zinc substitution. Fourier transform infrared spectroscopy (FTIR) spectra of the Ni1-xZn xFe2O4 with x = 0, 0.5, 1 in the range 400 - 4000 cm-1 were reported. The spinel structure and the crystalline water adsorption of Ni1-xZn xFe2O4 nanoparticles were studied by using FTIR.

Ni1-xZn xFe2O4 (x = 0 to 1) nanoparticles of size less than 9 nm were prepared by a chemical coprecipitation method which could be used for ferrofluid preparation. XRD, VSM and DTA-TG (STA) were used to study the effect of variation in Zn substitution and its influence on particle size, magnetic properties such as M S, H C and Curie temperature, as well as on the water content. ICP was used to estimate Ni, Zn and Fe concentrations. The average crystallite size (DaveXR) of the particles was found to decrease from 8.95 to 6.92 nm with increasing zinc substitution. The lattice constant (a o) increased with increasing zinc substitution. The specific saturation magnetization (M S) of the particles was measured at room temperature. Magnetic parameters such as M S, Hc, and Mr were found to decrease with increasing zinc substitution. Estimation of the water content, which varies the Zn concentration, plays a vital role for the correct determination of cation contents. The Curie temperature was found to decrease with increasing zinc substitution.