Ultrahigh field-induced strain in lead-free ceramics

By Jiyue Wu, Haibin Zhang, Changgang Huang, Chiao-Wei Tseng, Nan Meng, V. Koval, Y. Chou, Zhen Zhang, Haixue Yan. 2020

139 citations recorded by the source corpus.

Abstract 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.

Subfields: Biomedical Engineering, Electronic, Optical and Magnetic Materials, Materials Chemistry

View Paper: https://www.semanticscholar.org/paper/98b88807a50e0feac39b5ec7bf5068cca2be8f9d