INFLUENCE OF SYNTHESIS CONDITIONS ON THE SIZE, MORPHOLOGY AND STRUCTURE OF IRON OXIDE PARTICLES

Abstract

The possibility to control the structure, size and morphology of iron oxide nanoparticles prepared by the sol-gel approach has been studied. Two procedures were used to obtain γ-Fe2O3 and Fe3O4 samples: i) spray pyrolysis of FeII + FeIII salt solutions or Fe3O4•nH2O colloidal solutions; ii) chemical precipitation of FeII or FeII + FeIII hydroxides with subsequent peptization of the sediment and drying. SiO2 sol, chloride ions and surface-active agents (surfactants) were added into starting solutions to modify the surface of the resulting iron oxide nanoparticles and to control their size. Structural features of the samples were examined by XRD, TEM and SEM, IR spectroscopy and Mössbauer spectroscopy