Changes in the Structure, Magnetization, and Resistivity of BaFe<sub>12–<i>x</i></sub>Ti<i><sub>x</sub></i>O<sub>19</sub>
Д.А. Винник, A.Yu. Starikov, В.Е. Живулин, К.А. Астапович, В. А. Турченко, T.I. Zubar, Sergei V. Trukhanov, J. Kohout, Tomáš Kmječ, O. S. Yakovenko, L. Yu. Matzui, A. S. B. Sombra, Di Zhou, Rajshree B. Jotania, Charanjeet Singh, Yujie Yang, А.В. Труханов
Abstract
BaFe 12– x Ti x O 19 hexaferrites up to x = 2.00 were fabricated in an ordinary ceramic way. Crystal structure parameters were isothermally defined at 300 K from the powder XRD by the Rietveld technique. The cell constants have nonmonotonic concentration dependence with a local minimum of a ∼ 5.886 Å and V ∼ 698.75 Å 3 at x = 1.00. The occupation mechanism of the titanium cations is confirmed. The Mössbauer investigation confirms such localization of Ti 4+ . Magnetization vs field measurements were realized at 300 K. The law of approach to saturation (LAS) was applied to determine the magnetic loop characteristics. These values decrease almost monotonically with an increase in titanium concentration and temperature. The minimum magnetic values were obtained for x = 2.00 at 300 K. Ac resistivity had a nonmonotonic growth dependence. Minimum ac resistivity was fixed for x = 0.50 at 300 K. As the frequency increases, the ac resistivity decreases, as the value of the band gap. The real part of permittivity ε / rises constantly with increasing temperature and falls with frequency increase for all of the compositions. Changes in the structure, magnetization, and ac resistivity of BaFe 12– x Ti x O 19 were made on the basis of changing charged states of iron ions and the occupation mechanism by titanium ions.