Structral characterisation of a novel lead free perovskite layer structure antiferroelectric Sr2-xLaxTa2-xTixO3 (x ~ 0.32)

Lead free antiferroelectric materials are the focus of much attention for the replacement of lead based materials in electronic devices, such as high energy storage capacitors, sensors, actuators. In this study, we present first lead free perovskite-like layer structure antiferroelectric material, strontium tantalum lanthanum titanate. The thermal variation of dielectric permittivity and dielectric loss indicate phase transitions from an antiferroelectric to a ferroelectric and finally to a paraelectric on heating. Using high resolution neutron diffraction, this study aims to establish accurate crystal models for the three phases and the relationship between them.

无铅反铁电材料因可替代电子器件中的含铅材料而受到广泛关注，这类器件涵盖高储能电容器、传感器与执行器。本研究首次报道了一款类钙钛矿（Perovskite）层状结构的无铅反铁电材料——锶钽镧钛酸盐。介电常数与介电损耗的热演化特性表明，该材料在升温过程中依次经历反铁电态→铁电态→顺电态的相变。本研究采用高分辨中子衍射技术，旨在为上述三个物相建立精确的晶体结构模型，并阐明各物相间的内在关联。