High saturation magnetization in La-Ce-Zn doped M-type Sr-hexaferrites

La-Ce-Zn-doped M-type Sr-hexaferries SroaLa(0.3-x)CexFe(11.7)Zn(0.3)O(19-d) (0 <= x <= 0.3) were synthesized by solid-state reaction in both air and nitrogen atmospheres. The increased saturation magnetization of similar to 78 emu/g, which is similar to 5% higher than that of La Zn-doped Sr-hexaferrite (Sr(0.7)La(0.3)Fe(11.7)Zn(0.)3O(19)), could be obtained when the Ce-doped powder samples (x >= 0.1) were either annealed in nitrogen at 1100 degrees C after calcination in air at 1200 degrees C or directly calcined in nitrogen at 1200 degrees C. The increased M-S over the practical limit (similar to 74 emu/g) is attributable to both the formation of magnetic composites with high-M-S spinel phases and the M-S increase of the M-type hexafenite itself caused by oxygen vacancies. (C) 2014 Elsevier Ltd and Techna Group S.r.l. All rights reserved.