Abstract
Ferroelectric polymers exhibit numerous advantages for flexible and wearable electromechanical applications. However, their piezoelectric coefficient d33 remains relatively low while most previous approaches to improve d33 mainly focus on intramolecular engineering. Other than using intramolecular approaches, here we describe an intermolecular crosslinking strategy to achieve markedly enhanced d33 of −95.0 picocoulombs per newton in crosslinked ferroelectric poly(vinylidene fluoride-co-trifluoroethylene) copolymers. First-principles calculations reveal that intermolecular crosslinking creates strong local conformational heterogeneity facilitating ease of bond rotation near the crosslinking sites, which leads to a flattened energy landscape, resulting in substantially improved d33 response. We show that crosslinking enabled by solution casting process enhances piezoelectric properties across a variety of crosslinking agents. Our work offers a facile platform for rational modulation of piezoelectricity of ferroelectric polymers, representing a crucial step towards large-scale manufacturing of lightweight, flexible, and scalable ferroelectric polymers for developing high-performance electromechanical devices.
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The source data for Figs. 1–4 in this work are provided in the Source Data file. Source data are provided with this paper. All data are available from the corresponding author upon request. Source data are provided with this paper.
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Acknowledgements
This research was supported by the National Natural Science Foundation of China (Grant No. 12274152 and 92366302, Y.L.), the Guangdong Basic and Applied Basic Research Foundation (2024A1515010483, Y.L.), and the initial financial support from HUST (Y.L.). This work is also supported by The Innovative Research Group Project of National Natural Science Foundation of China (High-performance manufacturing of polymer products, 52521002) and Guangdong Provincial Key Laboratory of Manufacturing Equipment Digitization (2023B1212060012). C.Y. Li is supported by the Postdoctor Project of Hubei Province under Grant Number 2025HBBSHCXB095. The authors would thank the Analytical and Testing Center of Huazhong University of Science and Technology for the technical assistance.
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Z.Y. and C.Y.L. contributed equally to this work. Y.L. conceived the idea, designed the research, and supervised the project. Z.Y. synthesized polymer films. Z.Y. collected XRD, XPS and FTIR. Y.L. and Z.Y. performed field-dependent XRD. Z.Y. performed swelling, TGA, DSC and XPS measurements. Z.Y. and Y.T.G. performed electrical, dielectric, and electromechanical measurements. C.Y.L. carried out DFT calculations under supervision by Y.L., Z.Y. and H.M.Z. analyzed the data. Y.L. and H.M.Z. wrote the manuscript with feedback from all authors.
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Yuan, Z., Li, C., Gong, Y. et al. Large piezoelectricity in crosslinked ferroelectric polymers. Nat Commun (2026). https://doi.org/10.1038/s41467-026-69998-6
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DOI: https://doi.org/10.1038/s41467-026-69998-6
