Abstract
Realizing the full potential of stretchable bioelectronics in wearables, biomedical implants and soft robotics necessitates conductive elastic composites that are intrinsically soft, highly conductive and strain resilient. However, existing composites usually compromise electrical durability and performance due to disrupted conductive paths under strain and rely heavily on a high content of conductive filler. Here we present an in situ phase-separation method that facilitates microscale silver nanowire assembly and creates self-organized percolation networks on pore surfaces. The resultant nanocomposites are highly conductive, strain insensitive and fatigue tolerant, while minimizing filler usage. Their resilience is rooted in multiscale porous polymer matrices that dissipate stress and rigid conductive fillers adapting to strain-induced geometry changes. Notably, the presence of porous microstructures reduces the percolation threshold (Vc = 0.00062) by 48-fold and suppresses electrical degradation even under strains exceeding 600%. Theoretical calculations yield results that are quantitatively consistent with experimental findings. By pairing these nanocomposites with near-field communication technologies, we have demonstrated stretchable wireless power and data transmission solutions that are ideal for both skin-interfaced and implanted bioelectronics. The systems enable battery-free wireless powering and sensing of a range of sweat biomarkers—with less than 10% performance variation even at 50% strain. Ultimately, our strategy offers expansive material options for diverse applications.
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The main data supporting the results in this study are available within the paper and its Supplementary Information. Source data for Figs. 1–5 are provided with this paper. Source data are provided with this paper.
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Acknowledgements
Z. Yan acknowledges financial support from the start-up fund of the University of Missouri-Columbia. Z. Yan, P.-Y.C. and J.X. acknowledge the National Institute of Biomedical Imaging and Bioengineering (award number R01EB033371). The human study was supported by Z. Yan’s start-up fund. W.G. acknowledges support from National Institutes of Health grants (R01HL155815 and R21DK13266). P.-Y.C. acknowledges financial support from NSF ECCS 2229659. I.O. acknowledges financial support from the start-up fund of the University of Missouri-Columbia.
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Z. Yan, Y.X., P.-Y.C. and Z. Ye conceived the idea and led research efforts. Y.X., Z. Ye, G.Z., Q.F., Z.C., J.L., M.Y., Y.R., Y.L., X.Q., L.S. and J.X. performed the experiments. J.L. conducted numerical simulations. I.O. and B.B. led animal studies and performed surgeries. Z. Yan, Y.X., Z. Ye and W.G. wrote the paper with assistance of the other coauthors.
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Nature Nanotechnology thanks Michael Dickey, Chengkuo Lee and Xuechang Zhou for their contribution to the peer review of this work.
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Supplementary Tables 1 and 2, Figs. 1–31, Notes 1–4, references and video captions.
Supplementary Video 1
Demonstration of PSPN mechanical resilience.
Supplementary Video 2
ECG recording with strain-insensitive PSPN electrical wires.
Supplementary Video 3
Wireless control of the implanted optoelectronic system.
Supplementary Video 4
Wireless powering of the implanted optoelectronic system.
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Xu, Y., Ye, Z., Zhao, G. et al. Phase-separated porous nanocomposite with ultralow percolation threshold for wireless bioelectronics. Nat. Nanotechnol. (2024). https://doi.org/10.1038/s41565-024-01658-6
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DOI: https://doi.org/10.1038/s41565-024-01658-6