Effect of Mn Doped on Structural, Optical, and Dielectric Properties of BiFe_1-MnO₃ for Efficient Antioxidant Activity

Manganese-doped bismuth ferrites were synthesized using the coprecipitation method with the green extract Azadirachta indica. Our incorporation of the transition element, manganese, into bismuth ferrites tackles the challenge of increased leakage current often observed in intrinsic bismuth ferrites. We gained key insights through a comprehensive examination of the structural, dielectric, and optical properties of these materials, utilizing Fourier transform infrared spectroscopy (FTIR), impedance spectroscopy, and UV-visible spectroscopy, respectively. The formation of an octahedral geometry was confirmed using the FTIR technique. UV-visible spectroscopy indicated that 2% Mn doping is optimal, while we obtained a low band gap energy (2.21 eV) and high refractive index (3.010) at this amount of doping. The manufactured materials exhibited the typical ferrite-like dielectric response, that is, the dielectric parameter gradually decreased as the frequency increased and then stayed constant in the high-frequency range. Using the diphenylpicrylhydrazyl (DPPH) free radical assay, we also examined the antioxidant activity of bismuth ferrites. We concluded that among different Mn-doped BiFeMnO₃-based nanomaterials, the 2 wt % Mn-doped BiFeMnO₃ shows the highest antioxidant activity. This finding substantiates the efficacy of the optimized material with regard to its potent antioxidant activity, positioning it as a promising candidate for potential biomedical applications.