Thermogravimetric and Magnetic Properties of Ni1-XZnxFe2O4 Nanoparticles Synthesized by Coprecipitation

Ni1-xZnxFe2O4 (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 MS, HC and Curie temperature, as well as on the water content. ICP was used to estimate Ni, Zn and Fe concentrations. The average crystallite size (D aveXR) 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 (MS) of the particles was measured at room temperature. Magnetic parameters such as MS, Hc, and M r 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