Effect of Lanthanum Additive on the Structural, Magnetic, and Morphological Properties of La_xNi_1-xFe₂O₄ Ferrite Prepared by Sol-Gel Method

Authors

• Awattif A. Mohammed, Department of Physics, College of Science, University of Baghdad, Baghdad, IraqFollow
• Farah T. M. Noori, Department of Physics, College of Science, University of Baghdad, Baghdad, IraqFollow

Abstract

Spinel ferrites are valued for their tunable electrical and magnetic properties. Rare-earth substitution, such as with La³⁺, is known to modify their cation distribution and magnetic interaction. In this study, La_xNi_1-xFe₂O₄ nanoparticles (x = 0.0, 0.5, 0.7, and 0.9) were synthesized via the sol-gel method. Their properties were characterized using X-ray diffraction (XRD), vibrating sample magnetometry (VSM), and field-emission scanning electron microscopy (FE-SEM). XRD confirmed a single-phase cubic spinel structure for all compositions. A gradual peak shift with increasing La³⁺ content indicated lattice expansion, attributable to the larger ionic radius of La³⁺ compared to Fe³⁺ and Ni²⁺. Crystallite size, calculated via the Scherrer equation, also increased with La³⁺ content. VSM measurement showed typical ferrimagnetic hysteresis loops. Saturation magnetization (Ms) decreased progressively as non-magnetic La³⁺ ions replaced magnetic Fe³⁺ and Ni²⁺ ions, reducing the number of active magnetic sites. This substitution consequently lowered the remnant magnetization (Mr) and coercivity (Hc). FE-SEM images revealed predominantly spherical particles with varying agglomeration, attributed to magnetic and surface forces. The grain size was consistent with XRD estimates. Higher La³⁺ concentration led to increased agglomeration, reduced shape regularity, and altered particle size distribution and porosity. These results demonstrate that La³⁺ addition induces significant structural changes, weakens magnetic performance, and alters surface morphology, providing valuable insights for tailoring La_xNi_1-xFe₂O₄ nanoparticles for technological applications.

Keywords

FE-SEM, Lanthanum nickel ferrite nanoparticles, Sol-gel method, VSM analysis, XRD

Subject Area

Physics

Article Type

Article

First Page

2967

Last Page

2979

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite this Article

Mohammed, Awattif A. and Noori, Farah T. M. (2026) "Effect of Lanthanum Additive on the Structural, Magnetic, and Morphological Properties of La_xNi_1-xFe₂O₄ Ferrite Prepared by Sol-Gel Method," Baghdad Science Journal: Vol. 23: Iss. 8, Article 20.
DOI: https://doi.org/10.21123/2411-7986.5389