Stabilization of perovskite phase and dielectric properties of 0.95PZN-0.05BT derived from mechanical activation

Abstract

0.95Pb(Zn1/3Nb2/3)O3-0.05BaTiO3 (0.95PZN-0.05BT) of perovskite structure has been successfully synthesized by mechanically activating a powder mixture of PbO, Nb2O5, ZnO, BaO, and TiO2. Nanosized 0.95PZN-0.05BT perovskite particles were triggered to form in the powder mixture mechanically activated for 20 h. The resulting perovskite phase undergoes a decomposition reaction to form pyrochlore phase with increasing heat treatment temperature over the range of 450 to 700 °C. Further increasing the heat treatment temperatures above 700 °C results in a recovery of the perovskite phase as a consequence of the stabilization of PZN by BaTiO3. Sintering at 1100 °C for 1 h led to approximately 94% perovskite phase and a sintered density of approximately 96% theoretical in 0.95PZN-0.05BT. Sintered 0.95PZN-0.05BT exhibits a peak dielectric constant of 14 000 and a dielectric loss of 0.02 at the Curie temperature of 98 °C when measured at a frequency of 100 Hz.