Hexagonal ferrite powder synthesis using chemical coprecipitation

Abstract

The formation mechanism of 3BaO·2CoO·12Fe 2O 3 (Co 2Z), 2BaO·2CoO·6Fe 2O 3 (Co 2Y) and BaO·6Fe 2O 3 (BaM) powders were prepared using chemical coprecipitation methods in this study using X-ray diffraction (XRD), thermo-gravimetry (TG), differential thermal analysis (DTA) and Fourier transform infrared spectroscopy (FTIR). It was found that the BaM phase was formed directly through the reaction of the preceding ɛ-Fe 2O 3 and amorphous BaCO 3 for BaM precursor. For the Co 2Y precursor, the intermediate phase, BaM, was obtained through the reaction of the earlier formed BaFe 2O 4 and α-Fe 2O 3. The Co 2Y phase was obtained through a BaM and BaFe 2O 4 reaction. However, for the Co 2Z precursors, the BaM phase was obtained directly from the BaCO 3 and amorphous iron hydroxide reaction, with no α-Fe 2O 3 and BaFe 2O 4 formed as intermediates. Co 2Z phase was obtained through the reaction of the two previous formed BaM and Co 2Y phases.