Synthesis of La-doped Mn0·6Zn0.4LaxFe2-xO4 and the study of its structural, electrical and magnetic properties for high frequency applications

Abstract

Lanthanum doped Mn–Zn Ferrite nanoparticles, Mn0·6Zn0.4LaxFe2-xO4 (x = 0.00–0.10 in steps of 0.02), employing oxides of raw materials has been prepared by the conventional solid state reaction (SSR) route. The structural characteristics of resulting ferrite products are investigated by powder X-ray diffraction (XRD) confirming the formation of spinal cubic crystal structure of Mn–Zn Ferrite with privileged orientation along (311). The crystallite size, lattice constant, dislocation density, strain and other microstructural parameters have been traced as a function of the La content (x). FTIR results demonstrate the existence of functional groups associated with Mn–Zn ferrite observing the corresponding peaks at 423 cm−1 and 529 cm−1. The Eg values are lying between 1.23 eV and 1.30 eV studied by exploiting UV–Vis absorption. The ferromagnetic behavior of Mn–Zn ferrite products has been found with the help of PPMS. The saturation magnetization (MS) of bare sample is much larger than that of doped ferrites and decreases with the increasing amount of La content. The coercivity (HC) increases with La introduction and the remnant magnetization reduces from 0.8447 emu/gm to 0.1436 for lower La content (x = 0.02), while it increases at higher La content (x = 0.04–0.10). Dielectric properties and AC resistivity have been extracted from the measurement of impedance analyzer at ambient temperature. The values of dielectric constant are found to be higher in bare Mn–Zn ferrite than La doped Mn–Zn ferrite products.

Keywords

• Mn-Zn ferrite
• La doping
• Solid state reaction
• FTIR
• Saturation magnetization
• Dielectric constant