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The extraordinary performances of phase-coexisting ferroelectrics are significantly affected by not only the phase constitution but also the motion of domain walls. The study on the role of phase coexistence in the formation of ferroelectric and ferroelastic domain microstructures is of great importance to explain the enhanced piezoelectric properties. In situ high-energy diffraction and the Rayleigh law are utilized to reveal the interplay of phase constitution and domain configuration to the macroscopic electromechanical coupling effect in the morphotropic phase boundary composition of 0.365BiScO 3 –0.635PbTiO 3 during the application of a weak electrical loading in the present study. It was found that anisotropic phase transition and domain switching occur in polycrystalline ferroelectric ceramics and a phase transition occurs dramatically beyond the coercive field. Taking into account the important role of coupled ferroelectric and ferroelastic domain microstructures, we conceived a configuration of monoclinic domains coexisting with and bridging the tetragonal domains. The existence of bridging domains would provide an insight into the interplay of the phase and domain and explains the piezoelectric performance in the vicinity of morphotropic phase boundaries.
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This content will become publicly available on December 1, 2025
Mapping domain structures near a grain boundary in a lead zirconate titanate ferroelectric film using X-ray nanodiffraction
The effect of an electric field on local domain structure near a 24° tilt grain boundary in a 200 nm-thick Pb(Zr0.2Ti0.8)O3bi-crystal ferroelectric film was probed using synchrotron nanodiffraction. The bi-crystal film was grown epitaxially on SrRuO3-coated (001) SrTiO324° tilt bi-crystal substrates. From the nanodiffraction data, real-space maps of the ferroelectric domain structure around the grain boundary prior to and during application of a 200 kV cm−1electric field were reconstructed. In the vicinity of the tilt grain boundary, the distributions of densities ofc-type tetragonal domains with thecaxis aligned with the film normal were calculated on the basis of diffracted intensity ratios ofc- anda-type domains and reference powder diffraction data. Diffracted intensity was averaged along the grain boundary, and it was shown that the density ofc-type tetragonal domains dropped to ∼50% of that of the bulk of the film over a range ±150 nm from the grain boundary. This work complements previous results acquired by band excitation piezoresponse force microscopy, suggesting that reduced nonlinear piezoelectric response around grain boundaries may be related to the change in domain structure, as well as to the possibility of increased pinning of domain wall motion. The implications of the results and analysis in terms of understanding the role of grain boundaries in affecting the nonlinear piezoelectric and dielectric responses of ferroelectric materials are discussed.
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- Award ID(s):
- 2025439
- PAR ID:
- 10578697
- Publisher / Repository:
- International Union of Crystallography, Wiley
- Date Published:
- Journal Name:
- Journal of Applied Crystallography
- Volume:
- 57
- Issue:
- 6
- ISSN:
- 1600-5767
- Page Range / eLocation ID:
- 1789 to 1799
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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