Structural, Microstructural, and Magnetic Studies on Magnesium (Mg2+)-Substituted CoFe2O4 Nanoparticles

The present work deals with the synthesis and characterizations of magnesium-substituted cobalt ferrite (Co 1−x Mg x Fe 2 O 4; x = 0.00, 0.25, 0.50, 0.75, 1.00) nanoparticles by sol-gel auto combustion method. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) techniques were used for the characterization of the prepared samples. The magnetic properties were studied through pulse field hysteresis loop technique at room temperature. The XRD patterns of all the samples show the reflection which belongs to the cubic spinel structure. The XRD analysis confirmed the single-phase formation of spinel structure for the present ferrite system. Various structural parameters such as tetrahedral ionic radius (r A), the octahedral ionic radius (r B), theoretical lattice constant (a th), hopping length (L A and L B), tetrahedral bond length (d AL), octahedral bond length (d BL), tetra edge (d AE) and octa edge (d BE) were calculated from the XRD data. The variation of these structural parameters in magnesium composition has been studied. The M-H curves recorded at room temperature exhibit a typical hysteresis loop indicating that the sample exhibits a magnetic nature, which decreases with an increase in Mg content x. The large coercivity (H c) values indicate a nanocrystalline nature of the present samples. The coercivity, saturation magnetization, remanence magnetization, and magneton number decreases with an increase in Mg content x.