Síntesis y caracterización de ferritas por el método de combustión en solución usando solventes eutécticos profundos : Síntesis y caracterización de ferritas de hierro por el método de combustión, usando etalina (cloruro de colina + etilenglicol) como solvente eutéctico profundo.

Abstract

Magnetite (Fe3O4) is a ferrite with inverse spinel cubic structure, composed of 72.4% Fe and 27.6% O2. This material exhibits magnetic properties, enabling various applications such as catalyzing reactions, forming ferrofluids, treating pollutants, among others. Therefore, the present study aimed to synthesize Fe3O4 through the combustion method in solution using the DES ethaline. To achieve this, the DES was prepared from a 2:1 ratio between C2H6O2 and ChCl. Subsequently, the synthesis was carried out by solution combustion using the Fe(NO3)2·6H2O precursor along with ethaline. The same methodology was applied at different temperatures (300, 400, and 500°C) in stoichiometric and 50% excess ethaline conditions. Samples were analyzed using X-ray diffraction (XRD), atomic absorption (AA), transmission electron microscopy (TEM), and nitrogen physisorption (BET method) techniques.. Synthesis at 300°C was found to be more efficient, yielding Fe3O4 contents of 34% and 30%. The sample with 50% excess ethaline at 300°C did not show a higher Fe3O4 content compared to stoichiometric synthesis. AA analysis yielded Fe contents similar to literature values and those obtained through XRD. TEM analysis revealed particle sizes smaller than 50 nm. Finally, BET surface areas were 48.13 and 13.67 m2/g for the tests conducted at 300°C stoichiometric and with 50% excess ethaline, respectively.