Abstract
Flat elastic sheets tend to display wrinkles and folds. From pieces of clothing down to two-dimensional crystals, these corrugations appear in response to strain generated by sheet compression or stretching, thermal or mechanical mismatch with other elastic layers, or surface tension. Extensively studied in metals, polymers and, — more recently — in van der Waals exfoliated layers, with the advent of thin single crystal freestanding films of complex oxides, researchers are now paying attention to novel microstructural effects induced by bending ferroelectric-ferroelastics, where polarization is strongly coupled to lattice deformation. Here we show that wrinkle undulations in BaTiO3 sheets bonded to a viscoelastic substrate transform into a buckle delamination geometry when transferred onto a rigid substrate. Using spatially resolved techniques at different scales (Raman, scanning probe and electron microscopy), we show how these delaminations in the free BaTiO3 sheets display a self-organization of ferroelastic domains along the buckle profile that strongly differs from the more studied sinusoidal wrinkle geometry. Moreover, we disclose the hierarchical distribution of a secondary set of domains induced by the misalignment of these folding structures from the preferred in-plane crystallographic orientations. Our results disclose the relevance of the morphology and orientation of buckling instabilities in ferroelectric free sheets, for the stabilization of different domain structures, pointing to new routes for domain engineering of ferroelectrics in flexible oxide sheets.
| Original language | English |
|---|---|
| Article number | 121080 |
| Journal | Acta Materialia |
| Volume | 293 |
| DOIs | |
| State | Published - Jul 1 2025 |
Funding
D.P. acknowledges funding from \u2018la Caixa\u2019 Foundation fellowship (ID 100010434). The authors acknowledge the Spanish Ministry of Industry, Economy and Competitiveness (MINECO) through Grants no PID2019\u2013108573GB-C21, PID2022\u2013140589NB-I00, PID2020\u2013112914RB-I00 and PID2023\u2013147211OB-C22 funded by Grant No MCIN/AEI/10.13039/501100011033. The Micro Raman imaging research was conducted as part of a user project at the Center for Nanophase Materials Sciences (CNMS), which is a US Department of Energy, Office of Science User Facility at Oak Ridge National Laboratory. Authors acknowledge the use of instrumentation financed through Grant IU16\u2013014206 (METCAM-FIB) to ICN2 funded by the European Union through the European Regional Development Fund (ERDF), with the support of the Ministry of Research and Universities, and Generalitat de Catalunya. The ICN2 is funded by the CERCA programme/Generalitat de Catalunya and by the Severo Ochoa Centres of Excellence Programme, funded by the Spanish Research Agency (AEI, CEX2021\u2013001214-S). The ICMAB is funded the Severo Ochoa Centres of Excellence Programme, funded by the Spanish Research Agency (AEI, CEX2023\u2013001263-S). The INMA is funded by the Severo Ochoa Centres of Excellence Programme (AEI, CEX2023\u2013001286-S). The authors acknowledge the European\u2019s Union Horizon 2020 research and innovation programme under Grant No 823713-ESTEEM3. This work was also funded from Regional Gobierno de Aragon through Project Nos. E13_23R, including FEDER funding. The authors also acknowledge the use of instrumentation as well as the technical advice provided by the National Facility ELECMI ICTS, node \u00ABLaboratorio de Microscopias Avanzadas (LMA)\u00BB at \u00ABUniversidad de Zaragoza\u00BB. The authors are grateful to Dr. Kapil Gupta for assistance with the Spectra electron microscope at the Joint Electron Microscopy Centre at ALBA synchrotron (JEMCA). D.P. acknowledges funding from \u2018la Caixa\u2019 Foundation fellowship (ID 100010434). The authors acknowledge the Spanish Ministry of Industry, Economy and Competitiveness (MINECO) through Grants no PID2019\u2013108573GB-C21, PID2022\u2013140589NB-I00, PID2020\u2013112914RB-I00 and PID2023\u2013147211OB-C22 funded by Grant No MCIN/AEI/10.13039/501100011033. The Micro Raman imaging research was conducted as part of a user project at the Center for Nanophase Materials Sciences (CNMS), which is a US Department of Energy, Office of Science User Facility at Oak Ridge National Laboratory. Authors acknowledge the use of instrumentation financed through Grant IU16\u2013014206 (METCAM-FIB) to ICN2 funded by the European Union through the European Regional Development Fund (ERDF), with the support of the Ministry of Research and Universities, and Generalitat de Catalunya. The ICN2 is funded by the CERCA programme/Generalitat de Catalunya and by the Severo Ochoa Centres of Excellence Programme, funded by the Spanish Research Agency (AEI, CEX2021\u2013001214-S). The ICMAB is funded the Severo Ochoa Centres of Excellence Programme, funded by the Spanish Research Agency (AEI, CEX2023\u2013001263-S). The INMA is funded by the Severo Ochoa Centres of Excellence Programme (AEI, CEX2023\u2013001286-S). The authors acknowledge the European's Union Horizon 2020 research and innovation programme under Grant No 823713-ESTEEM3. This work was also funded from Regional Gobierno de Aragon through Project Nos. E13_23R, including FEDER funding. The authors also acknowledge the use of instrumentation as well as the technical advice provided by the National Facility ELECMI ICTS, node \u00ABLaboratorio de Microscopias Avanzadas (LMA)\u00BB at \u00ABUniversidad de Zaragoza\u00BB. The authors are grateful to Dr. Kapil Gupta for assistance with the Spectra electron microscope at the Joint Electron Microscopy Centre at ALBA synchrotron (JEMCA).
Keywords
- Buckling
- Ferroelastic-ferroelectrics
- Freestanding oxides
- Hierarchical domain structures