Highly conductive, stretchable and biocompatible ag–au core–sheath nanowire composite for wearable and implantable bioelectronics

ABSTRACT Wearable and implantable devices require conductive, stretchable and biocompatible materials. However, obtaining composites that simultaneously fulfil these requirements is

challenging due to a trade-off between conductivity and stretchability. Here, we report on Ag–Au nanocomposites composed of ultralong gold-coated silver nanowires in an elastomeric

block-copolymer matrix. Owing to the high aspect ratio and percolation network of the Ag–Au nanowires, the nanocomposites exhibit an optimized conductivity of 41,850 S cm−1 (maximum of

72,600 S cm−1). Phase separation in the Ag–Au nanocomposite during the solvent-drying process generates a microstructure that yields an optimized stretchability of 266% (maximum of 840%).

The thick gold sheath deposited on the silver nanowire surface prevents oxidation and silver ion leaching, making the composite biocompatible and highly conductive. Using the nanocomposite,

we successfully fabricate wearable and implantable soft bioelectronic devices that can be conformally integrated with human skin and swine heart for continuous electrophysiological

recording, and electrical and thermal stimulation. Access through your institution Buy or subscribe This is a preview of subscription content, access via your institution ACCESS OPTIONS

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Contact customer support SIMILAR CONTENT BEING VIEWED BY OTHERS EVAPORATION-INDUCED SELF-ASSEMBLED ULTRATHIN AGNW NETWORKS FOR HIGHLY CONFORMABLE WEARABLE ELECTRONICS Article Open access 07

May 2024 PHASE-SEPARATED STRETCHABLE CONDUCTIVE NANOCOMPOSITE TO REDUCE CONTACT RESISTANCE OF SKIN ELECTRONICS Article Open access 16 January 2024 HIGH-PERFORMANCE AG2SE-BASED

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37, 711–718 (1958). Article  Google Scholar  Download references ACKNOWLEDGEMENTS This work was supported by the Institute for Basic Science (grant numbers IBS-R006-D1 and IBS-R006-A1). The

authors thank the staff of the National Center for Inter-university Research Facilities (NCIRF) and the Research Institute of Advanced Materials (RIAM) in Seoul National University. The

authors also thank M. Josephson for material and intellectual support of the animal research. AUTHOR INFORMATION Author notes * These authors contributed equally: Suji Choi, Sang Ihn Han,

Dongjun Jung, Hye Jin Hwang. AUTHORS AND AFFILIATIONS * Center for Nanoparticle Research, Institute for Basic Science (IBS), Seoul, Republic of Korea Suji Choi, Sang Ihn Han, Dongjun Jung, 

Chaehong Lim, Ok Kyu Park, Mincheol Lee, Taeghwan Hyeon & Dae-Hyeong Kim * School of Chemical and Biological Engineering, Institute of Chemical Processes, Seoul National University,

Seoul, Republic of Korea Suji Choi, Sang Ihn Han, Dongjun Jung, Chaehong Lim, Ok Kyu Park, Mincheol Lee, Ji Woong Yu, Ji Ho Ryu, Won Bo Lee, Taeghwan Hyeon & Dae-Hyeong Kim *

Cardiovascular Division, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA Hye Jin Hwang, Soochan Bae, Cory M. Tschabrunn, Sun Youn Bae, Peter M. Kang & Reza

Nezafat * Department of Physiology, School of Dentistry, Seoul National University, Seoul, Republic of Korea Sang-Woo Lee & Kyungpyo Park Authors * Suji Choi View author publications You

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S.C., S.I.H., D.J., H.J.H., T.H. and D.-H.K. designed the experiments. S.C., S.I.H., D.J., C.L., M.L., H.J.H., T.H. and D.-H.K. performed experiments and analysis. S.C., S.I.H., D.J.,

H.J.H., C.L., S.B., O.K.P., C.M.T., S.Y.B., S.-W.L., K.P., P.M.K. and R.N. performed in vivo animal experiments and data analysis. S.I.H., S.-W.L. and K.P. performed in vitro experiments and

analysis. J.W.Y., J.H.R. and W.B.L. performed computer simulations. S.C., S.I.H., D.J., H.J.H., S.B., T.H. and D.-H.K. wrote the paper. CORRESPONDING AUTHORS Correspondence to Taeghwan

Hyeon or Dae-Hyeong Kim. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. ADDITIONAL INFORMATION PUBLISHER’S NOTE: Springer Nature remains neutral with

regard to jurisdictional claims in published maps and institutional affiliations. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary figures 1–15, Supplementary References

SUPPLEMENTARY VIDEO The heat rolling-pressed Ag–Au nanocomposite was stretched to 200%, 400% and 840% RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE

Choi, S., Han, S.I., Jung, D. _et al._ Highly conductive, stretchable and biocompatible Ag–Au core–sheath nanowire composite for wearable and implantable bioelectronics. _Nature Nanotech_

13, 1048–1056 (2018). https://doi.org/10.1038/s41565-018-0226-8 Download citation * Received: 19 February 2018 * Accepted: 10 July 2018 * Published: 13 August 2018 * Issue Date: November

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