Samiksha Verma, O. P. Pandey, Andrea Paesano Júnior e Puneet Sharma

Physica B: Condensed Matter – Volume: 448; Pages: 57-59; DOI: 10.1016/j.physb.2014.03.035

Effect of La3+ substitution on structural and magnetic properties of Ba1−xLaxFe12O19 (x=0.0-0.2) prepared by two different methods was studied. For the first method, La3+ substituted BaFe12O19 has been directly prepared by solid state synthesis of Fe2O3 and BaCO3 at Fe/Ba molar ratio of 6. For the second method, solid state synthesis of Fe2O3 and Ba1−xLaxFe2O4 at molar composition of 5:1 has been adopted. As-prepared powders were characterized by X-ray diffraction, Mössbauer spectroscopy and vibration sample magnetometry. XRD patterns were refined by the Rietveld analysis method. Single phase barium hexaferrite was obtained by both the methods with a minor amount of residual hematite. Ba1−xLaxFe12O19 prepared from Ba1−xLaxFe2O4 showed higher magnetization (M) which was the maximum for x=0.1, without any remarkable change in the coercivity. The increase in M is attributed to increase in hyperfine field for 12k, 4f1, 4f2, 2a and 2b sites.