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.

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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

  1. These authors contributed equally: Suji Choi, Sang Ihn Han, Dongjun Jung, Hye Jin Hwang.

Affiliations

  1. 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
  2. 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
  3. 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
  4. Department of Physiology, School of Dentistry, Seoul National University, Seoul, Republic of Korea

    • Sang-Woo Lee
    •  & Kyungpyo Park

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Contributions

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.

Competing interests

The authors declare no competing interests.

Corresponding authors

Correspondence to Taeghwan Hyeon or Dae-Hyeong Kim.

Supplementary information

  1. Supplementary Information

    Supplementary figures 1–15, Supplementary References

  2. Supplementary Video

    The heat rolling-pressed Ag–Au nanocomposite was stretched to 200%, 400% and 840%

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DOI

https://doi.org/10.1038/s41565-018-0226-8