Effect of M2+ Ions on the Magnetic, Dielectric and Optical Properties of MFe2O4(M-Co, Ba) Ferrites

Abstract

In this work, we synthesized pristine CoFe2O4 and BaF2O4 and investigate their structural, optical, dielectric and magnetic properties. Both CoFe2O4 and BaFe2O4 were prepared via the citric acid-assisted sol-gel auto combustion method. X-ray diffraction studies were performed to elucidate the structure of these samples. A computer program called Qualx software is used to identify the crystal phases and the presence of impurities. From the database, It is seen that CoFe2O4 exhibits a mixed spinel cubic structure with a space group Fd-3m and BaFe2O4 exhibits an orthorhombic structure with a space group Cmc21. Rietveld refinement analysis is performed to obtain a complete picture of crystal structure and cation distribution. It is observed that CoFe2O4 exhibit a centrosymmetric structure having two origins from octahedral and tetrahedral sites and BaFe2O4 have a centrosymmetric structure. The position and occupancy of the atoms in both compounds are identified. Williamson Hall method is employed to study the crystallite size and induced strain in CoFe2O4 and BaFe2O4 material. Optical properties were identified by UV-Visible spectroscopy. The low density of defect states is observed in BaFe2O4. BaFe2O4 exhibit low dielectric permiitivity and low tangent loss in room temperature. Isothermal M-H loop at room temperature shows that CoFe2O4 exhibit a ferrimagnetism and BaFe2O4 exhibit a ferrimagnetism with antiferromagnetism.