PREPARATION OF DISSIMILARLY STRUCTURED FERRITE COMPOUNDS BY SOL-GEL AUTO-COMBUSTION METHOD

Abstract

Ferrites with the spinel-type NiFe₂O₄ (NiF), CoFe₂O₄ (CoF) and hexagonal BaFe₁₂O₁₉ (BaM) structure were obtained using the auto-combusting reaction method. After the temperature-initiated auto-combusting reaction, different oxide mixtures were obtained. In the next step by calcination at 800 °C for BaM and CoF and at 1000 °C for NiF, corresponding ferrite compounds of a high level of purity were obtained. Auto-combustion reaction temperature was determined by thermogravimetry (TG) analysis. The obtained substances (crystalline phases) and their crystallite size were investigated by X-ray diffraction (XRD) analysis. Powder-forming particle sizes were characterized by atomic force microscopy (AFM) and by scanning electron microscopy (SEM). AFM images revealed particles of nanometer dimensions under 50 nm.