Improvements of dielectric properties of Fe doped TbMnO3

The ceramic composites of Tb1−xFexMnO3 (x=0.05, 0.1, 0.2, 0.3, 0.4) were synthesized by conventional solid-state reaction. The dielectric constants and loss of composites as a function of temperature (from 77 to 350 K) and frequency (from 0.1 to 200 kHz) were measured. Interestingly, in all composites, Tb0.95Fe0.05MnO3 sample not only enjoys the highest dielectric constants (~104) in the high temperature and low frequency range, but also presents the lowest loss in the high frequency range. Debye-like dielectric dissipation peaks shift to high temperature range with the increase of frequency, which become unobvious in high iron content doping samples. Analysis indicates that the perovskite structures gradually change with the increase of Fe content and the dielectric properties of TbMnO3 can be improved by adding Fe with appropriate content.