Ultrahigh field-induced strain in lead-free ceramics
Ultrahigh field-induced strain in lead-free ceramics
复制标题
DOI：
10.1016/j.nanoen.2020.105037
复制
发表时间：
2020-10
期刊：
影响因子：
17.6
通讯作者：
Jiyue Wu;Haibin Zhang;Changgang Huang;Chiao-Wei Tseng;Nan Meng;V. Koval;Y. Chou;Zhen Zhang
中科院分区：
文献类型：
--
作者：
Jiyue Wu;Haibin Zhang;Changgang Huang;Chiao-Wei Tseng;Nan Meng;V. Koval;Y. Chou;Zhen Zhang
由于环境保护和可持续发展的全球性关注，无铅压电材料是非常需要的电能和机械能的桥梁。然而，与传统的含铅压电材料相比，它们较低的能量转换系数显著限制了它们的器件应用。在此，我们介绍了一种新的策略，通过材料结构设计，以增加无铅铁电系统的应变，在材料中创建极性纳米区域（PNR）和点缺陷，同时保留全局铁电相。这种在材料中增加的短程结构不均匀性将促进场诱导相变和可逆畴壁切换以增强应变。根据这一策略，我们证明了一个无织构无铅Bi0.5Na0.5TiO3（BNT）基陶瓷的电场诱导的应变。在70 kV/cm时，单极模式下的应变（Suni）可高达0.74%，是迄今为止报道的无铅陶瓷中的最高值。这为利用材料结构工程设计高性能压电材料提供了一条很好的途径。这也揭示了无铅压电材料在实际机电器件应用中的潜力。
Due to the worldwide concerns of environmental protection and sustainable development, lead-free piezoelectric materials are greatly desired for bridging the electrical energy to the mechanical energy. However, their lower energy conversion coefficient compared to the conventional lead-containing piezoelectric materials significantly limits their device applications. Herein, we introduce a novel strategy to increase the strain of lead-free ferroelectric system via material structure design to create polar nano regions (PNRs) and point defects in the material while retaining the global ferroelectric phase. This added short-range structural heterogeneity in the material will facilitate the field-induced phase transition and reversible domain wall switching to enhance the strain. Following this strategy, we demonstrate an ultrahigh strain induced by an electric field in non-textured lead-free Bi0.5Na0.5TiO3(BNT)-based ceramics. The strain in unipolar mode (Suni) can reach up to 0.74% at 70 kV/cm, making it the highest value in reported lead-free ceramics so far. This puts forward a good route to design high-performance piezoelectric materials by material structure engineering. It also reveals the promising potential of lead-free piezoelectric materials in practical electromechanical device applications.