International Journal of Science and Technology (IJST)

The Structural, Vibrational, Morphological, Optical, and Magnetic Property Studies of Nickel-Doped Manganese Ferrite (Ni₀.₃Mn₀.₇Fe₂O₄) Nanoparticles

This study investigated the structural, vibrational, morphological, optical, and magnetic properties of nickel-doped manganese ferrite (Ni₀.₃Mn₀.₇Fe₂O₄) nanoparticles synthesized via co-precipitation route. X-ray diffraction patterns confirmed the formation of a single-phase cubic spinel structure, Fourier Transform Infrared spectroscopy reveals two characteristic absorption bands, corresponding to metal-oxygen stretching vibrations at the tetrahedral and octahedral sites, respectively. Nickel substitution induces a noticeable shift in these bands toward higher wavenumbers, indicating modified vibrational modes. Morphological analysis using Field Emission Scanning Electron Microscopy shows spherical to irregular grain shapes with distinct grain boundaries and increased particle agglomeration at higher doping levels. UV-Visible spectroscopy demonstrates tuning of the optical band gap, with a shift in absorption edge influenced by nickel concentration. Photoluminescence analysis exhibits emission peaks in the visible region, which is attributed to oxygen vacancies and electronic transitions between the octahedral site e_g orbital and the O(2p) level. Finally, Vibrating Sample Magnetometer measurements reveal a systematic variation in saturation magnetization (M_s) and coercivity (H_c). These integrated results highlight the efficacy of nickel doping in engineering multifunctional Mn-ferrite nanoparticles for advanced optoelectronic and magnetic applications.