Structural, Optical, Magnetic, and Electrical Properties of Samarium (Sm3+)-Doped Copper–Iron Oxide Ferrites for Possible Optoelectronic Applications

Herein we report the effect of samarium (rare earth metal) doping on the morphological, structural, optical, magnetic, dielectric, and electrical properties of copper–iron oxide ferrite composites [CuFe2−xSmxO4 (x = 0, 0.05, 0.075, and 0.1)] (abbreviated as SCFO). The CuFe2−xSmxO4-based ferrites were synthesized by the solution combustion technique. The morphological and structural features and elemental composition of these doped ferrites were characterized by scanning electron microscopy (SEM), energy dispersive x-ray spectroscopy (EDS), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and UV-visible spectroscopy. The analysis revealed improved structural features for (Sm3+)-doped copper–iron oxide ferrites and the formation of a homogeneous composite structure. Doping of a rare earth metal (Sm3+) into the Cu–Fe–O ferrite significantly enhanced the room-temperature electrical conductivity of the doped ferrite in comparison to its pure counterpart. The energy band gap value of the higher-concentration sample was found to decrease significantly in comparison to the pure ferrite due to enhanced charge density across the grain boundaries. Further, it was observed that (Sm3+) doping led to improved optical, magnetic, and dielectric response of the doped ferrites which was dependent on the concentration of the dopant. The dielectric constant of these doped ferrites was found to be higher at lower frequencies and decreased dramatically with increased frequencies due to the greater dielectric dispersion as well as electron hopping in the higher-frequency region. The magnetic properties showed strong dependence on both the sintering temperature and concentrations of (Sm3+) doping. The optical bandgap decreased significantly with the increase in concentration of (Sm3+) doping. In light of the ease of synthesis, improved electrical conductivity, and dielectric, magnetic, and optical properties, these SCFO ferrites hold promise as a potential material for optoelectronic applications.