Paraelectric Behavior of 0 . 75 ( Na 0 . 5 Bi 0 . 5 ) TiO 3-0 . 25 SrTiO 3 Under Induced Electric-Field

Perovskite compounds, such as lead zirconate titanate Pb(Zr,Ti)O3 or PZT, have attracted significant interest for applications in actuators, capacitors, sensors, and transducers, where high strain, dielectric constant and piezoelectric coefficient are desired. PZT is commercially available in a variety of products, however, the lead content remains an environmental concern, which has motivated researchers to seek alternative, lead-free perovskite compounds. Sodium bismuth titanate, (Na0.5Bi0.5)TiO3 (NBT), among other lead-free perovskites, has been recognized as a potential replacement for PZT in some commercial applications. NBT exhibits ferroelectric behavior at room temperature, and becomes paraelectric at temperatures above 520 °C, which manifests through a crystallographic phase change from rhombohedral (ferroelectric) to tetragonal (paraelectric).