Magnetic property and cation distributions in boron-doped MFe2O4(M = Ni, Mn) spinel ferrites

Abstract

(A)[B]2O4 spinel ferrites with initial compositions, BxM1−xFe2O4 (M = Ni or Mn), were prepared using the solid state reaction technique. X-ray photoelectron spectra indicate that there were only 25% of boron ions in the end samples while the remaining boron ions were lost in the thermal treatment process. Therefore, the end samples have a composition of Bx1Mx2Fe3−x1−x2O4 (M = Ni or Mn). X-ray diffraction patterns showed that the end samples possess a single-phase cubic spinel structure. For the two series of samples, the observed dependencies on the boron content, x1, of the sample magnetic moments at 10 K were fitted successfully by using the quantum mechanical potential barrier model. The cation distributions were obtained in the fitting process, during which the magnetic moment direction of the Mn3+ cations was assumed to anti-ferromagnetically couple with those of other cations whenever they are at the (A) or [B] sites in the samples, according to the O 2p itinerant electron model.