Synthesis and characterization of FeSe۲ nanoparticles and FeSe۲/FeO(OH) nanocomposites by hydrothermal method

چکیده مقاله

FeSe2 nanoparticles and FeSe2/FeO(OH) nanocomposites have been synthesized through a novel controllable hydrothermal method with FeSO47H2O and SeCl4 as precursors. In this procedure, H2SeO3 (obtained from aqueous solution of SeCl4) is gradually reduced to Se and Se2 by reductant. The reduced Se and Se2 ions are combined with Fe2+ ion to give FeSe2. By varying the surfactant, reaction time, temperature, reductant and amount of hydrazine hydrate (N2H4H2O), the method permits us to synthesize different products. The FeSe2 nanoparticles are synthesized in the presence of PEG4000 at 140 C for 13 h. Using PEG600 (at 140 C or 110 C for 13 h) and sodium dodecyl sulfate (at 140 C for 7 h), FeSe2/FeO(OH) nanocomposites are synthesized. SEM and TEM images show the morphology and size of the as-synthesized samples. Chemical composition of the samples is characterized by XRD, XPS and EDS. Ultraviolet–visible and photoluminescence spectra exhibit optical properties of nanostructures. Magnetization measurement shows a twofold behavior, ferromagnetic and paramagnetic behaviors, for FeSe2 nanoparticles.