A facile one-step green hydrothermal synthesis of paramagnetic Fe3O4 nanoparticles with highly efficient dye removal

Background: The aim of this study was the characterization of hydrothermal green synthesized Fe3O4 nanoparticles, as an attractive metal oxide with paramagnetic properties, mediated with Myrtus communis (myrtle) extract. Method: The effect of myrtle extract and iron sulfate concentration were assessed on the properties of synthesized nanoparticles. Also, the nanoparticles were synthesized without extract to evaluate the extract effect on the reaction. Significant findings: The obtained results of X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive X-ray (EDX) were in good agreement with each other. The spherical, cubic, and polygonal shapes were created in the chemical method and monodispersed spheres were only observed in green synthesis at all precursor concentrations. The maximum saturation magnetization (Ms) values were obtained about 41 emu.g(- 1) and 91 emu.g(-1) for green and chemically synthesized Fe3O4 nanoparticles, respectively. In addition, green synthesized Fe3O4 nanoparticles indicated high removal capacity for cationic methylene blue (MB), as well as anionic Congo red (CR) dyes compared with chemically synthesized Fe3O4 nanoparticles. The maximum of adsorbed dye per unit mass of adsorbent was 18 mg.g(-1) for both dyes. The excellent adsorption capacity, paramagnetic properties, and uniform shape make the green Fe3O4 nanoparticles as an attractive adsorbent.