Synthesis of Nano-Crystalline Barium Hexaferrite Using a Reactive Co-Precipitated Precursor

Abstract

Nano-crystalline particles of barium hexaferrite have been prepared by co-precipitation route using solution of iron and barium chlorides with a Fe/Ba molar ratio of 12 by addition of NaOH with OH-/Cl- molar ratio of 2. A mixture of water and diethylene glycol with volume ratio of 1:3 was used as a solvent in the process. Dried co-precipitated powder was annealed at various temperatures for 1 h. FTIR, XRD, DTA/TGA, SEM, and TEM techniques were used to evaluate powder particle characteristics. DTA/TGA results confirmed by those obtained from XRD indicated that the formation of barium hexaferrite occurs at relatively low temperature of 614 degC for precursor synthesized in diethylene glycol/water solution. The corresponding mean crystallite size measured by TEM for sample annealed at 700degC was 35 nm.