Intergrowth Bi_2WO_6-Bi_3TiNbO_9 ferroelectrics with high ionic conductivity

摘要

Two dielectric relaxation loss peaks associated with oxygen-ion diffusion in the intergrowth Bi_2WO_6-Bi_3TiNbO_9(Bi_5TiNbWO_(15)) bismuth layered ferroelectrics were observed. The activation energy and the relaxation time at infinite temperature, for these two peaks, were determined to be (0.89 eV, 1.3 X 10~(-13) s) and (0.84 eV, 3.6 X 10~(10) s). The ac impedance spectroscopy indicated that the Bi_5TiNbWO_(15) ceramic is an ionic conductor with an electrical conductivity of approximately 2.6 X 10~(-2) S/cm at a temperature of 1073 K.