Crystal structure and magnetic properties of LaFe_1-xNi_xO₃ nanomaterials prepared via a simple co-precipitation method

In this paper, nanostructured Ni-doped LaFeO₃ materials were prepared via a simple co-precipitation method involving the hydrolysis of La(III), Fe(III), and Ni(II) cations in hot water with 5% KOH as a precipitating agent. To evaluate the effects of Ni substitution in these products, their structural phases, lattice parameters, crystallite and grain sizes, and magnetic properties were determined. As the Ni content in the LaFe_1-xNi_xO₃ (x = 0–0.25) materials increased, the average crystallite size and lattice parameters decreased. Moreover, across the range of Ni-substitution ratios, all magnetic properties correspondingly changed: the coercive force (H_c) value rose from 42.53 to 173.98 Oe. In contrast, the remanent magnetization (M_r) and saturation magnetization (M_s) values decreased from 1.0· × 10⁻² to 3.8· × 10⁻⁴ emu g⁻¹, and from 0.24· × 10° to 0.74· × 10⁻⁴ emu g⁻¹, respectively. These predictable changes provide a sound foundation for the fabrication and application of magnetic materials based on nanostructured Ni-doped LaFeO₃ substrates.