Green Synthesis of Magnetite (Fe sub(3)O sub(4)) Nanoparticles Using Seaweed (Kappaphycus alvarezii) Extract

In this study, a simple, rapid, and eco-friendly green method was introduced to synthesize magnetite nanoparticles (Fe sub(3)O sub(4)-NPs) successfully. Seaweed Kappaphycus alvarezii (K. alvarezii) was employed as a green reducing and stabilizing agents. The synthesized Fe sub(3)O sub(4)-NPs were characterized with X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-Vis), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM) techniques. The X-ray diffraction planes at (220), (311), (400), (422), (511), (440), and (533) were corresponding to the standard Fe sub(3)O sub(4) patterns, which showed the high purity and crystallinity of Fe sub(3)O sub(4)-NPs had been synthesized. Based on FT-IR analysis, two characteristic absorption peaks were observed at 556 and 423 cm super(-1), which proved the existence of Fe sub(3)O sub(4) in the prepared nanoparticles. TEM image displayed the synthesized Fe sub(3)O sub(4)-NPs were mostly in spherical shape with an average size of 14.7 nm.