Computational and experimental study on cation distribution of Cobalt substituted barium hexaferrites BaFe12-xCoxO19 (x=0, 0.3, 0.6, 0.9) for circulator applications

The anisotropic BaFe12-xCoxO19 (x = 0, 0.3, 0.6, 0.9) (BFCO) samples were synthesized. We investigated the crystal structure, microstructure, and magnetic properties of BFCO. And the potential application value at millimeter waveband was discussed. The magnetic anisotropy field is successfully decrease from 17 kOe to 10 kOe by substituting Cobalt, which lower the Ferromagnetic resonance frequency and benefit for extending the bandwidth for the circulator. With the cobalt substitution, the saturation inevitably decreases from 60 emu/g to 45 emu/g. The site preference of cobalt in five crystallographically inequivalent Fe ions was calculated using software castep. The influence of site preference on lattice parameters and magnetic saturation was calculated and discussed. The result show cobalt mainly sites 2a and 12k position. (c) 2021 Published by Elsevier B.V.

Automated summary

The anisotropic BaFe12-xCoxO19 samples were synthesized and their crystal structure, microstructure, and magnetic properties were investigated. The potential application value of these samples at millimeter waveband was discussed. Substituting Cobalt successfully decreased the magnetic anisotropy field and saturation, and the site preference of cobalt in different Fe ions was calculated and discussed.