The effect of lanthanum substitution on the structural, magnetic, and dielectric properties of nanocrystalline Mn-Ni spinel ferrite for radio frequency (RF) applications

Abstract

The Sol-gel auto-combustion method is used to synthesize nanocrystalline Mn-Ni spinel ferrites substituted with lanthanum. The crystallite size of the samples decreases from 29.16 nm to 19.98 nm as La+3 ions are added. The saturation magnetization ranges between 54.13 and 69.19 emu/g, and the coercivity ranges from 33.56 to 62.00 Oe. Thus, they could be used in electromagnets and in suppression of electromagnetic noise as soft magnetic materials. The dielectric constant of the specimens decreases with the addition of La+3 ions. Therefore, the La-doped samples with low dielectric constant can be employed in radio frequency equipment. The substituted ferrites have high resistivity and saturation magnetization, which leads to high power density and low power loss in the inductors, contributing to energy savings.