Role of Nature of Rare Earth Ion Dopants on Structural, Spectral, and Magnetic Properties in Spinel Ferrites

Abstract

In this research work, the effect of ionic radii of various rare earth ions on structural and magnetic properties of spinel ferrites having the composition MFe2-yREyO4 (y = 0, 0.2) (where M = Cu, Cd, Ni, Zn, Mn, and RE = La, Ce, and Tb and Dy) have been studied. XRD reflections for Tb3+/Dy3+ and Ce3+ substitution ensured phase purity of FCC structure formation with no additional impurities. But we have observed secondary phases for lanthanum substituted spinel ferrites due to its larger ionic radii as compared to host crystal. Crystallite sizes and lattice parameters are found to show decreasing trend with decreasing ionic radii of dopant rare earth ions. The magnetic parameters for all prepared samples were discussed by tracing hysteresis curves measured at room temperature. VSM data demonstrated that magnetization of investigated samples was found to be increased with substitution of larger ionic radii ions which is attributed to spin-canting effect and increase of crystallite. Furthermore, the dopants having smaller ionic radii have possessed high coercivity and improved initial permeability. On the basis of these characteristics, these synthesized materials could be suggested for various industrial and technological applications.