Synthesis of antiferroelectric (Bi0.534Na0.5)0.94Ba0.06TiO3 ceramics with high phase transition temperature and broad temperature range by a solid-state reaction method

Abstract

Antiferroelectric 0.94(Bi0.534Na0.5)TiO3-0.06BaTiO3 ceramics were prepared using a solid-state reaction method, involving the addition of excessive amounts of Bi2O3. The resulting ceramics featured a very high phase transition temperature (Tm ∼330°C), from the antiferroelectric to the paraelectric phase, and a low depolarization temperature (Td < 25°C). The broad temperature range, within which antiferroelectric properties are retained, of the prepared materials indicates their higher potential over lead-based antiferroelectric ceramics such as PZT-based materials that exhibit a lower Tm ⩽ 170°C. The lower Td and higher Tm obtained values, relative to those reported in the literature, are believed to be due to the formation of A-site vacancies originating from the incorporation of excess Bi into the perovskite structure of the studied sample. In addition, the synthesized sample shows a high dielectric constant of ∼1460, in a temperature range of 50–150°C at 1 kHz, and a high energy storage density of 0.71 J/cm3, which is an asset in energy storage capacitor applications.