Structural, Optical, Magnetic and Dielectric Properties of CoFe12O19 Synthesized in the Presence of Moringa oleifera Flower Extract

In this study, a unique approach was employed to synthesize M-type cobalt hexaferrite (CoFe12O19) using Moringa oleifera flower extract as a green capping agent. For 3 h, the calcination procedure was conducted at 1100 ºC. It was found that the structural, optical, microstructural, magnetic and dielectric properties of the generated cobalt hexaferrite were considerably affected by the presence of phytochemicals in floral extract. To evaluate the structural, surface morphological, optical, magnetic and dielectric properties of prepared ferrite, a variety of characterization techniques including FT-IR, XRD, UV-Vis, SEM, VSM and dielectric techniques were applied. The XRD analysis showed the formation of a hexagonal phase along with hematite and cobalt ferrite, while the surface morphology showed hexagonal shaped platelet structure. With a saturation magnetization (Ms) of 14.94 emu/g and a coercivity (Hc) of 1790.9 Oe, the CoFe12O19 powder demonstrated a multidomain nature, which is a magnetically hard material. Furthermore, the energy bandgap of the cobalt ferrite was observed to be 2.01 eV. Low frequency dielectric measurement was carried out at room temperature and ε′max ~ 46 found at 30 Hz with tan δ equals to 0.103. The dielectric behaviour with frequency follows the Koop’s model and Maxwell-Wagner theory. One semicircle arc was observed in Cole-Cole plot.