Hexagonal ferrite powder synthesis using chemical coprecipitation

The formation mechanism of 3BaO·2CoO·12Fe2O3 (Co2Z), 2BaO·2CoO·6Fe2O3 (Co2Y) and BaO·6Fe2O3 (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-Fe2O3 and amorphous BaCO3 for BaM precursor. For the Co2Y precursor, the intermediate phase, BaM, was obtained through the reaction of the earlier formed BaFe2O4 and α-Fe2O3. The Co2Y phase was obtained through a BaM and BaFe2O4 reaction. However, for the Co2Z precursors, the BaM phase was obtained directly from the BaCO3 and amorphous iron hydroxide reaction, with no α-Fe2O3 and BaFe2O4 formed as intermediates. Co2Z phase was obtained through the reaction of the two previous formed BaM and Co2Y phases.