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Title: Near-ideal electromechanical coupling in textured piezoelectric ceramics
Abstract

Electromechanical coupling factor,k, of piezoelectric materials determines the conversion efficiency of mechanical to electrical energy or electrical to mechanical energy. Here, we provide an fundamental approach to design piezoelectric materials that provide near-ideal magnitude ofk, via exploiting the electrocrystalline anisotropy through fabrication of grain-oriented or textured ceramics. Coupled phase field simulation and experimental investigation on <001> textured Pb(Mg1/3Nb2/3)O3-Pb(Zr,Ti)O3ceramics illustrate thatkcan reach same magnitude as that for a single crystal, far beyond the average value of traditional ceramics. To provide atomistic-scale understanding of our approach, we employ a theoretical model to determine the physical origin ofkin perovskite ferroelectrics and find that strong covalent bonding between B-site cation and oxygen viad-phybridization contributes most towards the magnitude ofk. This demonstration of near-idealkvalue in textured ceramics will have tremendous impact on design of ultra-wide bandwidth, high efficiency, high power density, and high stability piezoelectric devices.

Authors:
; ; ; ; ; ;
Publication Date:
NSF-PAR ID:
10368129
Journal Name:
Nature Communications
Volume:
13
Issue:
1
ISSN:
2041-1723
Publisher:
Nature Publishing Group
Sponsoring Org:
National Science Foundation
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