Synthesis and magnetic properties of nanostructured Ni_(1-x)Zn_xFe_2O_4(x = 0.4, 0.5 and 0.6)

摘要

Nanostructured Ni_(1-x)Zn_xFe_2O_4(x = 0.4, 0.5 and 0.6) samples are prepared by the auto-combustion method. The compounds are formed in the cubic spinel phase without any impurity as confirmed by the XRD data. Increase in lattice parameters and volume of the unit cell with the Zn content is observed which is due to the larger ionic sizes of Zn~(2+) (0.74 A) and Ni~(2+) (0.69 A) when compared with that of Fe~(3+) (0.60 A). The crystallite size increased with the Zn content. FESEM analysis reveals a non-uniform size distribution in grain sizes with the Zn content. All the prepared compounds maintained (Ni, Zn) and Fe stoichiometry in the ratio close to 1:2 as observed from the EDAX measurements. Magnetic properties are investigated using a VSM magnetometer. The magnetic parameters, such as saturation magnetization (Ms), coercive field (Hc), remnant magnetization (Mr) and Bohr magneton (μB), are determined. The saturation magnetization decreases gradually with increase in the Zn concentration.