Controlled synthesis and phase characterization of Fe-based nanoparticles obtained by thermal decomposition

Iron oxide nanoparticles were synthesized by the thermal decomposition of Fe(acac)(3) and Fe(CO)(5). Three different homogeneous procedures were used for the controlled synthesis of Fe3O4, gamma-Fe2O3 and Fe3O4/ gamma-Fe2O3 mixture nanocrystals. A combination of characterization techniques was used in order to distinguish these oxides. The controllable size, the narrow distribution and the rhombic self-assembly of the nanoparticles were revealed by the high-resolution transmission electron microscopy images and the X-ray powder diffraction results. For the quantitative analysis of the samples manganometry was used. Preliminary magnetic measurements indicated the size and composition dependence of saturation magnetization, a superparamagnetic behavior of the samples and some ferromagnetic features. (c) 2007 Elsevier B.V. All rights reserved.