Fabrication and Structural Characterization of La-Doped Cobalt Ferrites

Abstract

A series of lanthanum-doped cobalt ferrite (CoFe₂O₄) nanoparticles were prepared and well characterized to examine how the replacement of rare-earth ions affected the structural and optical characteristics of spinel ferrites. The production was conducted through solution-phase pathways with a focus on the environment-friendly and cost-efficient methods. The structural characterization was done through X-ray diffraction (XRD) and it established the existence of single phase cubic spinel structure with the incorporation of La³⁺ ions into the cobalt ferrite structure being successful. The differences in the lattice parameters and the size of crystallites were a sign of lattice distortion due to the increased ionic radius of the La³⁺ ions with respect to the Fe³⁺ ions. The scanning electron microscopy (SEM) was used to analyze surface morphology, and particle distribution, which indicated moderate agglomeration of nanoscale particles. The optical properties were studied by using the UV-visible spectroscopy where a broad absorption in the UV-visible was found and typical of ferrite nanoparticles. There was a visible shift in the absorption edge with an increase in lanthanum concentration, which suggests that the electronic structure and band gap energy were changed. The findings show that lanthanum doping causes substantial changes in the structural and optical properties of cobalt ferrite nanoparticles and they are promising in their usage in magnetic, optical, and electronic devices. This paper underscores the usefulness of controlled doping as an approach in order to customize the characteristics of spinel ferrites to high-technology functional uses.