Effect of La Doping on Structural and Magnetic Properties of SrLa_xFe_12−xO₁₉ Ceramics from Aqueous Solution Method

Abstract

Influences of different amount of La-substituted on structural and magnetic properties of M-type strontium ferrites SrLaxFe(12−x)O19 compounds prepared by an aqueous solution method have been systematically investigated by XRD, VSM and TEM. In this work, it is found that only magnetoplumbite structure exists in the sample rather minorphases from the XRD patterns. When the doping content is x≤0.06mol, substituting of La3+ for Fe3+ occurs, forming SrLaxFe(12-x)O19. In contrast, when the doping content is x>0.06mol, Sr2+ is substituted by La3+, forming Sr(1-x)LaxFe12O19. The saturation magnetization (σs) shows its maximum at x=0.04 while the peak value of the intrinsic coercive field (Hjc) presented at x=0.06 as the La substituted content increases. The obtained results also indicated that the shape of the formed SrLaxFe(12−x)O19 is oblong with 70nm length and 40nm width.