Structure and Dielectric Properties of Homogeneous Sr_m-3Bi₄Ti_mO_3m+3 (m = 3, 4, 5, and 6) Ceramics

Srm-3Bi4TimO3m+3 (m =3, 4, 5, and 6) bulk ceramics were prepared by conventional solid-state reaction process. Their phase structures and morphologies were observed by XRD and SEM respectively. The dielectric properties and hysteresis loops of the ceramics were measured by impedance analyzer and hysteresis meter respectively. Results showed that the lattice parameters along the c axis are 32.79, 41.11, 48.83, and 58.17Ǻ for m=3, 4, 5, and 6 respectively. The microstructures of plate-like crystalline phases are shown in all the ceramics with different m. Curie temperature of Srm-3Bi4TimO3m+3 decreases from 668°C to 295°C with increasing m from 3 to 6. The remnant polarizations Pr are 32.46 and 19.44 μC/cm2 for odd m of 3 and 5, and 11.84 and 10.58 μC/cm2 for even m of 4 and 6 respectively.