Ultrahigh Piezoelectric Properties in Textured (K,Na)NbO3 -Based Lead-Free Ceramics

Peng Li; Jiwei Zhai; Bo Shen; Shujun Zhang; Xiaolong Li; Fangyuan Zhu; Xingmin Zhang

doi:10.1002/adma.201705171

Ultrahigh Piezoelectric Properties in Textured (K,Na)NbO₃ -Based Lead-Free Ceramics

Adv Mater. 2018 Feb;30(8). doi: 10.1002/adma.201705171. Epub 2018 Jan 10.

Authors

Peng Li¹, Jiwei Zhai¹, Bo Shen¹, Shujun Zhang², Xiaolong Li³, Fangyuan Zhu³, Xingmin Zhang³

Affiliations

¹ Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai, 201804, China.
² Institute for Superconducting and Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong, NSW, 2500, Australia.
³ Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai, 201204, China.

PMID: 29318671
DOI: 10.1002/adma.201705171

Abstract

High-performance lead-free piezoelectric materials are in great demand for next-generation electronic devices to meet the requirement of environmentally sustainable society. Here, ultrahigh piezoelectric properties with piezoelectric coefficients (d₃₃ ≈700 pC N^-1 , d₃₃ * ≈980 pm V^-1 ) and planar electromechanical coupling factor (k_p ≈76%) are achieved in highly textured (K,Na)NbO₃ (KNN)-based ceramics. The excellent piezoelectric properties can be explained by the strong anisotropic feature, optimized engineered domain configuration in the textured ceramics, and facilitated polarization rotation induced by the intermediate phase. In addition, the nanodomain structures with decreased domain wall energy and increased domain wall mobility also contribute to the ultrahigh piezoelectric properties. This work not only demonstrates the tremendous potential of KNN-based ceramics to replace lead-based piezoelectrics but also provides a good strategy to design high-performance piezoelectrics by controlling appropriate phase and crystallographic orientation.

Keywords: crystal orientation; nanodomains; textured ceramics; ultrahigh piezoelectric properties.