Bulletin of the Chemical Society of Japan · 1979 · 36 citations · 6 references
Natural SciencesChemistryMaterials ScienceInorganic ChemistryMagnetic MaterialsPhysical ChemistryFerrimagnetic MaterialsFerromagnetic MaterialsFerromagnetismMagnetic CeramicsMagnetic OxidesMagnetic Properties Of SolidsFerrite SpinelsFerritesMagnetiteMagnetite FormationOxidationPh DependenceSpinel FerritesSpinel Structure
Abstract When the Cd2+/Fetotal ratio in the initial solution is below 0.1, almost all cadmium ions are incorporated into the ferrite with the spinel-type structure by the air oxidation of an aqueous suspension at a pH 9.0 and at 65 °C. The Cd-bearing ferrite thus obtained is a ferromagnet and is oxidized to form a completely oxidized Cd-bearing ferrite at 150 °C in the air; this ferrite is still a ferromagnet and belongs to the Fe2O3–CdFe2O4 binary system, with the same spinel type structure. When the Cd2+/Fetotal ratio in the initial solution increases to 0.5, the crystalline phases formed is complicatedly changed; the products are also significantly affected by the pH value of the suspension. The most favorable pH value at 65 °C to form the Cd-bearing ferrite is proposed to be 10.0.
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