Publication Type:Journal Article
Source:Nature Nanotechnology, Nature Publishing Group, Volume 6, Number 2, p.98-102 (2011)
Keywords:Article, bismuth, bismuth compounds, electric activity, Electric-field-induced strain, ferric oxide, Field-induced strain, health hazard, Health risks, High resolution transmission electron microscopy, In situ processing, In-situ transmission electron microscopies, iron compounds, lead, Lead-based materials, Lead-free piezoelectric materials, Mechanical actuators, Mechanical response, Morphotropic phase boundaries, nanoanalysis, Piezoelectric actuators, Piezoelectric materials, piezoelectricity, priority journal, Sensors and actuators, Strain, transmission electron microscopy
Piezoelectric materials exhibit a mechanical response to electrical inputs, as well as an electrical response to mechanical inputs, which makes them useful in sensors and actuators1. Lead-based piezoelectrics demonstrate a large mechanical response, but they also pose a health risk2. The ferroelectric BiFeO3 is an attractive alternative because it is lead-free, and because strain can stabilize BiFeO3 phases with a structure that resembles a morphotropic phase boundary3. Here we report a reversible electric-field-induced strain of over 5% in BiFeO 3 films, together with a characterization of the origins of this effect. In situ transmission electron microscopy coupled with nanoscale electrical and mechanical probing shows that large strains result from moving the boundaries between tetragonal- and rhombohedral-like phases, which changes the phase stability of the mixture. These results demonstrate the potential of BiFeO3 as a substitute for lead-based materials in future piezoelectric applications. © 2011 Macmillan Publishers Limited. All rights reserved.
cited By 217