Dielectric Properties and Relaxation of Bi2Ti2O7

The dielectric properties of Bi₂Ti₂O₇ were explored as a function of temperature and frequency. A comparison between the dielectric response of the well‐known Bi_1.5Zn_0.92Nb_1.5O_6.92 (BZN) pyrochlore and the recently available Bi₂Ti₂O₇ sintered ceramic revealed considerable differences, which indicate that chemical disorder, and not atomic displacement on its own, is chiefly responsible for the dielectric relaxation in bismuth pyrochlores. A low‐frequency (<10 kHz) and relatively high‐temperature (~125 K) dielectric relaxation was observed in Bi₂Ti₂O₇. An Arrhenius function was used to model the relaxation behavior and yielded an activation energy of 0.162 eV and an attempt jump frequency of ~1 MHz. This response is consistent with space charge polarization and not the result of dipolar or ionic disorder.