Effect of In3+ substitution on structural and magnetic properties of Ni ferrite nanoparticles

NiInxFe2−xO4 (x=0.0, 0.1, 0.2, 0.3, 0.4) ferrite nanoparticles have been synthesized by sol-gel autocombustion technique. The effect of In3+ substitution on the structural and magnetic properties of nickel ferrite has been analyzed by X-ray diffraction (XRD), Fourier transform infrared spectra (FTIR), Field emission scanning electron microscopy (FESEM) and Vibrating sample magnetometer (VSM). The XRD results confirmed the formation of single cubic spinel phase for 0≤x≤0.3 and the appearance of secondary phase of In2O3 for x=0.4. The lattice parameter increases (from 8.3152 to 8.4336 Å) with indium content. The FTIR results illustrated that the absorption intensity of peak at about 594 cm−1 increases with increasing the In3+ ions. The saturation magnetization increases and then decreases while the coercivity decreases along with In3+substitution. The maximal saturation magnetization emerged at the composition of NiIn0.2Fe1.8O4 (42.111 emu/g).