Billah Motasim, Terasawa Yukana, Masud Mostafa Kamal, Asahi Toru, Hegazy Mohamed Barakat Zakaria, Nagata Takahiro, Chikyow Toyohiro, Uesugi Fumihiko, Hossain Md Shahriar A, Yamauchi Yusuke
Australian Institute for Bioengineering and Nanotechnology (AIBN), The University of Queensland Brisbane QLD 4072 Australia
School of Mechanical and Mining Engineering, Faculty of Engineering, Architecture and Information Technology (EAIT), The University of Queensland Brisbane QLD 4072 Australia.
Chem Sci. 2024 May 20;15(24):9147-9154. doi: 10.1039/d3sc06712b. eCollection 2024 Jun 19.
Lattice strain effects on the piezoelectric properties of crystalline ferroelectrics have been extensively studied for decades; however, the strain dependence of the piezoelectric properties at nano-level has yet to be investigated. Herein, a new overview of the super-strain of nanoporous polycrystalline ferroelectrics is reported for the first time using a nanoengineered barium calcium zirconium titanate composition (BaCa)(TiZr)O (BCZT). Atomic-level investigations show that the controlled pore wall thickness contributes to highly strained lattice structures that also retain the crystal size at the optimal value (<30 nm), which is the primary contributor to high piezoelectricity. The strain field derived from geometric phase analysis at the atomic level and aberration-corrected high-resolution scanning transmission electron microscopy (STEM) yields of over 30% clearly show theoretical agreement with high piezoelectric properties. The uniqueness of this work is the simplicity of the synthesis; moreover the piezoresponse becomes giant, at around 7500 pm V. This response is an order of magnitude greater than that of lead zirconate titanate (PZT), which is known to be the most successful ferroelectric over the past 50 years. This concept utilizing nanoporous BCZT will be highly useful for a promising high-density electrolyte-free dielectric capacitor and generator for energy harvesting in the future.
几十年来，晶格应变对晶体铁电体压电性能的影响已得到广泛研究；然而，纳米级压电性能的应变依赖性尚未得到研究。在此，首次使用纳米工程化的钡钙锆钛酸盐组合物（BaCa）（TiZr）O（BCZT）报道了纳米多孔多晶铁电体超应变的新概述。原子级研究表明，可控的孔壁厚度有助于形成高度应变的晶格结构，该结构还能将晶体尺寸保持在最佳值（<30nm），这是高压电性的主要贡献因素。原子级几何相位分析和像差校正高分辨率扫描透射电子显微镜（STEM）得出的应变场超过30%，清楚地表明与高压电性能在理论上是一致的。这项工作的独特之处在于合成方法的简单性；此外，压电响应变得巨大，约为7500 pm V。该响应比锆钛酸铅（PZT）大一个数量级，PZT在过去50年里一直是最成功的铁电体。利用纳米多孔BCZT的这一概念对未来有望用于能量收集的高密度无电解质介电电容器和发电机将非常有用。
