Abstract
Fine barium hexaferrite (BaFe12O19) powder consisting of platelike particles with the magnetoplumbite structure, 30–60 nm in size, is synthesized at 550°C via rapid oxidation of a suspension of barium and iron(II) hydroxides with NaClO. The magnetic properties of BaFe12O19 powders prepared by modified coprecipitation and spray pyrolysis processes are described. The coercivity of fine BaFe12O19 powders is shown to be lower than that of bulk material, which is due to the presence of a magnetically inactive layer of noncollinear spins in the basal plane of the hexagonal particles. BaFe12O19 particles less than 10 nm in size are shown to be in a superparamagnetic state.
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Pankov, V.V. Synthesis of BaFe12O19 Powder by Modified Coprecipitation and Spray Pyrolysis Methods. Inorganic Materials 40, 979–984 (2004). https://doi.org/10.1023/B:INMA.0000041333.79255.1f
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DOI: https://doi.org/10.1023/B:INMA.0000041333.79255.1f