Structural and magnetic properties of sol-gel synthesized (1-x) Mn_0.5Cu_0.25Zn_0.25Fe₂O₄ + (x)SrCe_0.05Sm_0.05Fe_11.9O₁₉ soft-hard ferrite nano composites

This paper presents a comprehensive investigation into the structural and magnetic properties of (1-x) Mn_0.5Cu_0.25Zn_0.25Fe₂O₄ + (x) SrCe_0.05Sm_0.05Fe_11.9O₁₉ soft-hard ferrite nanocomposites. The resulting materials were characterized using various techniques including X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), and vibrating sample magnetometry (VSM). Structural analysis confirmed the coexistence of soft and hard phases within the composites without additional phases or structural diffusion. Rietveld refinement of XRD data provided precise structural information, revealing variations in lattice parameters and crystallite sizes with changing composition. Specifically, the lattice parameter “a” for the MCZFO phase ranged from 8.3881  to 8.4393 Å, while for the SCSFO phase, “a” ranged from 5.8846  to 5.9326 Å and “c” from 22.8714  to 23.2493 Å. SEM images depicted the microstructure of the composites, indicating the presence of cubic and hexagonal-shaped particles with some aggregation. EDAX analysis confirmed the elemental composition of the composites, consistent with the intended stoichiometry. TEM images further supported the structural analysis, revealing particle aggregation and crystalline phases. FTIR spectra displayed characteristic absorption bands of the ferrite phases, with shifts observed upon varying compositions. VSM analysis demonstrated complex magnetic behavior with significant changes in magnetic parameters. The saturation magnetization varied in the range of 57.90  to 48.23 emu/g, while remanent magnetization increased from 1.12  to 35.42 emu/g, and coercivity dramatically rose from 14.96  to 7160 Oe as the proportion of the hard phase increased. These findings offer valuable insights into the structural and magnetic characteristics of soft-hard ferrite composites, providing a basis for developing tailored magnetic materials for diverse technological applications.