Structural Crystallinity and Optical Behaviour of MgFe₂O₄ Ferrite Nanoparticles Prepared by Sol–Gel Method

Magnesium ferrite (MgFe₂O₄) nanoparticles are promising soft magnetic materials with significant application potential in magnetic storage, microwave devices, catalysis, and optoelectronic systems. In the work, MgFe₂O₄ nanoparticles were synthesized using a sol–gel method. Metal nitrates were used as precursors, with citric acid as a chelating agent, followed by gelation, drying, and calcination to obtain the final ferrite powder. The structural properties were examined using X-ray diffraction (XRD), which confirmed the formation of crystalline MgFe₂O₄ with a well-developed spinel structure. The crystallinity increased from approximately 70% to 93%, indicating the improved of structural ordering. The crystallite size was evaluated using both Debye–Scherrer and Williamson–Hall method varies between ~2nm and ~ 29 nm across the samples, demonstrating size tunability through synthesis and processing conditions. UV–Vis spectroscopy was employed to investigate the optical absorption behaviour. The obtained results confirm successful synthesis of nanocrystalline MgFe₂O₄ for multifunctional technological applications.