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

Abstract

Nickel ferrites are ferrimagnetic materials recognized for their electrical, magnetic, optical, and chemical stability properties, thus used in catalytic processes, environmental remediation, and various devices. This study examines the influence of temperature and the amount of ethaline used in the synthesis of nickel ferrites by solution combustion. For the synthesis, tests were conducted at temperatures of 300, 400 and 500°C for two variants, one using stoichiometric ratios between the nickel salt and the fuel ethaline, and another with 25% excess of ethaline. Characterization included X-ray diffraction (XRD), nitrogen physisorption, atomic absorption (AA) and transmission electron microscopy (TEM) analyses. The analyses showed best results at 500°C, with samples of inverse spinel crystal structure and uniform crystals. Morphological and surface analysis revealed spherical structures with particle sizes between 14 and 34 nm and specific surface area (SBET) of 15.57 m2/g, for the sample synthesized with stoichiometric ratios, and cubic structures with sizes varying from 15 to 55 nm, and SBET of 26.58 m2/g, for the sample in which excess ethaline was used. However, the chemical analysis showed for both cases a nickel deficiency, so it is determined that the temperature and the amount of ethaline had significantly affected the obtained ferrites properties.