Spinel Iron Oxide by the Co-Precipitation Method: Effect of the Reaction Atmosphere

Synthesis atmosphere (i.e., air and nitrogen) effects on the physical properties formation mechanism of spinel iron oxide nanoparticles prepared via co-precipitation method have been investigated using a multi-technique approach. The obtained magnetic (MNPs) were characterized X-ray diffraction, transmission electron microscopy (TEM), SQUID magnetometry, Mössbauer spectroscopy absorption near-edge Structure techniques. synthesis procedure leads to structure with an average crystallite size 9.0(9) nm. morphology particles synthetized under inert was quasi-spherical, while in present faceted shape. small differences observed morphological are explained by influence reaction MNPs. characterization indicates that both samples exhibit superparamagnetic behavior at 300 K. investigation means Langevin approach K also equal values for mean cores (Dm). Additionally, analysis spectra revealed lack spin disorder samples, resulting high saturation magnetization. fit XANES spectrum suggests about 2/3 ions reside local environment close γ-Fe2O3 1/3 Fe3O4 sample atmosphere.