Skip to main content

Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

  • Article
  • Published:

Strain-resilient electrical functionality in thin-film metal electrodes using two-dimensional interlayers

Nature Electronics volume 4, pages 126–133 (2021)Cite this article

Subjects

Abstract

Flexible electrodes that allow electrical conductance to be maintained during mechanical deformation are required for the development of wearable electronics. However, flexible electrodes based on metal thin films on elastomeric substrates can suffer from complete and unexpected electrical disconnection after the onset of mechanical fracture across the metal. Here we show that the strain-resilient electrical performance of thin-film metal electrodes under multimodal deformation can be enhanced by using a two-dimensional interlayer. Insertion of atomically thin interlayers—graphene, molybdenum disulfide or hexagonal boron nitride—induces continuous in-plane crack deflection in thin-film metal electrodes. This leads to unique electrical characteristics (termed electrical ductility) in which electrical resistance gradually increases with strain, creating extended regions of stable resistance. Our two-dimensional interlayer electrodes can maintain a low electrical resistance beyond a strain at which conventional metal electrodes would completely disconnect. We use the approach to create a flexible electroluminescent light-emitting device with an augmented strain-resilient electrical functionality and an early damage diagnosis capability.

This is a preview of subscription content, access via your institution

Access options

Buy this article

  • Purchase on Springer Link
  • Instant access to full article PDF
Buy now

Prices may be subject to local taxes which are calculated during checkout

Fig. 1: Flexible metal electrode achieved by the insertion of a 2D material interlayer.
Fig. 2: Fracture behaviours of thin-film metal electrodes with 2D interlayers.
Fig. 3: Strain-resilient electrical performance with 2D interlayers.
Fig. 4: Flexible light-emitting device integrated with an electromechanically robust metal–2D interconnector.

Similar content being viewed by others

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.

References

  1. Gao, W., Ota, H., Kiriya, D., Takei, K. & Javey, A. Flexible electronics toward wearable sensing. Acc. Chem. Res. 52, 523–533 (2019).

    Article  Google Scholar 

  2. Akinwande, D., Petrone, N. & Hone, J. Two-dimensional flexible nanoelectronics. Nat. Commun. 5, 5678 (2014).

    Article  Google Scholar 

  3. Hong, G. & Lieber, C. M. Novel electrode technologies for neural recordings. Nat. Rev. Neurosci. 20, 330–345 (2019).

    Article  Google Scholar 

  4. Ray, T. R. et al. Bio-integrated wearable systems: a comprehensive review. Chem. Rev. 119, 5461–5533 (2019).

    Article  Google Scholar 

  5. Pang, C., Lee, C. & Suh, K. Recent advances in flexible sensors for wearable and implantable devices. J. Appl. Polym. Sci. 130, 1429–1441 (2013).

    Article  Google Scholar 

  6. Koh, A. et al. A soft, wearable microfluidic device for the capture, storage and colorimetric sensing of sweat. Sci. Transl. Med. 8, 366ra165 (2016).

    Article  Google Scholar 

  7. Robinson, A. P., Minev, I., Graz, I. M. & Lacour, S. P. Microstructured silicone substrate for printable and stretchable metallic films. Langmuir 27, 4279–4284 (2011).

    Article  Google Scholar 

  8. Nathan, A. et al. Flexible electronics: the next ubiquitous platform. Proc. IEEE 100, 1486–1517 (2012).

    Article  Google Scholar 

  9. Graudejus, O., Go, P. & Wagner, S. Controlling the morphology of gold films on poly(dimethysiloxane). ACS Appl. Mater. Interfaces 2, 1927–1933 (2010).

    Article  Google Scholar 

  10. Gerratt, A. P., Michaud, H. O. & Lacour, S. P. Elastomeric electronic skin for prosthetic tactile sensation. Adv. Funct. Mater. 25, 2287–2295 (2015).

    Article  Google Scholar 

  11. Rogers, J. A., Someya, T. & Huang, Y. Materials and mechanics for stretchable electronics. Science 327, 1603–1607 (2010).

    Article  Google Scholar 

  12. Decataldo, F. et al. Stretchable low impedance electrodes for bioelectronic recording from small peripheral nerves. Sci. Rep. 9, 10598 (2019).

    Article  Google Scholar 

  13. Song, E. et al. Flexible electronic/optoelectronic microsystems with scalable designs for chronic biointegration. Proc. Natl Acad. Sci. USA 116, 15398–15406 (2019).

    Article  Google Scholar 

  14. Lu, N. & Kim, D. Flexible and stretchable electronics paving the way for soft robotics. Soft Robot. 1, 53–62 (2013).

    Article  Google Scholar 

  15. Lacour, S. P., Wagner, S., Huang, Z. & Suo, Z. Stretchable gold conductors on elastomeric substrates. Appl. Phys. Lett. 82, 2404–2406 (2003).

    Article  Google Scholar 

  16. Lu, N., Wang, X., Suo, Z. & Vlassak, J. Metal films on polymer substrates stretched beyond 50%. Appl. Phys. Lett. 91, 221909 (2007).

    Article  Google Scholar 

  17. Baëtens, T., Pallecchi, E., Thomy, V. & Arscott, S. Cracking effects in squashable and stretchable thin metal films on PDMS for flexible microsystems and electronics. Sci. Rep. 8, 9492 (2018).

    Article  Google Scholar 

  18. Beuth, J. L. Cracking of thin bonded films in residual tension. Int. J. Solids Struct. 29, 1657–1675 (1992).

    Article  Google Scholar 

  19. Wang, J., Cheng, Q. & Tang, Z. Layered nanocomposites inspired by the structure and mechanical properties of nacre. Chem. Soc. Rev. 41, 1111–1129 (2012).

    Article  Google Scholar 

  20. Yin, Z., Hannard, F. & Barthelat, F. Impact-resistant nacre-like transparent materials. Science 364, 1260–1263 (2019).

    Article  Google Scholar 

  21. Kim, Y. et al. Strengthening effect of single-atomic-layer graphene in metal–graphene nanolayered composites. Nat. Commun. 4, 2114 (2013).

    Article  Google Scholar 

  22. Oh, S. H., Ryu, S. & Han, S. M. Role of graphene in reducing fatigue damage in Cu/Gr nanolayered composite. Nano Lett. 17, 4740–4745 (2017).

    Article  Google Scholar 

  23. Hutchinson, J. W. & Suo, Z. Mixed mode cracking in layered materials. Adv. Appl. Mech. 29, 63–191 (1991).

    Article  Google Scholar 

  24. Kruzic, J. J., Nalla, R. K., Kinney, J. H. & Ritchie, R. O. Crack blunting, crack bridging and resistance-curve fracture mechanics in dentin: effect of hydration. Biomaterials 24, 5209–5221 (2003).

    Article  Google Scholar 

  25. Chowdhury, P. & Sehitoglu, H. Mechanisms of fatigue crack growth—a critical digest of theoretical developments. Fatigue Fract. Eng. Mater. Struct. 39, 652–674 (2016).

    Article  Google Scholar 

  26. Suh, Y. D. et al. Random nanocrack, assisted metal nanowire-bundled network fabrication for a highly flexible and transparent conductor. RSC Adv. 6, 57434–57440 (2016).

    Article  Google Scholar 

  27. Nam, K. H., Park, I. H. & Ko, S. H. Patterning by controlled cracking. Nature 485, 221–224 (2012).

    Article  Google Scholar 

  28. Leterrier, Y., Pinyol, A., Rougier, L., Waller, J. H. & Mnson, J. A. E. Electrofragmentation modeling of conductive coatings on polymer substrates. J. Appl. Phys. 106, 113508 (2009).

    Article  Google Scholar 

  29. Zhang, S., Ma, T., Erdemir, A. & Li, Q. Tribology of two-dimensional materials: from mechanisms to modulating strategies. Mater. Today 26, 67–86 (2019).

    Article  Google Scholar 

  30. Hess, P. Prediction of mechanical properties of 2D solids with related bonding configuration. RSC Adv. 7, 29786–29793 (2017).

    Article  Google Scholar 

  31. Polikov, V. S., Tresco, P. A. & Reichert, W. M. Response of brain tissue to chronically implanted neural electrodes. J. Neurosci. Methods 148, 1–18 (2005).

    Article  Google Scholar 

  32. Niu, S. et al. A wireless body area sensor network based on stretchable passive tags. Nat. Electron. 2, 361–368 (2019).

    Article  Google Scholar 

  33. Jia, H. et al. Single- and few-layer transfer-printed CVD MoS2 nanomechanical resonators with enhancement by thermal annealing. In Proc. 2016 IEEE International Frequency Control Symposium (IFCS) 1–3 (IEEE, 2016).

  34. Wu, X. et al. Growth of continuous monolayer graphene with millimeter-sized domains using industrially safe conditions. Sci. Rep. 6, 21152 (2016).

    Article  Google Scholar 

  35. Cao, C. et al. Nonlinear fracture toughness measurement and crack propagation resistance of functionalized graphene multilayers. Sci. Adv. 4, eaao7202 (2018).

    Article  Google Scholar 

  36. Zhang, P. et al. Fracture toughness of graphene. Nat. Commun. 5, 3782 (2014).

    Article  Google Scholar 

  37. Stuart, S. J., Tutein, A. B. & Harrison, J. A. A reactive potential for hydrocarbons with intermolecular interactions. J. Chem. Phys. 112, 6472–6486 (2000).

    Article  Google Scholar 

  38. Van Duin, A. C. T., Dasgupta, S., Lorant, F. & Goddard, W. A. ReaxFF: a reactive force field for hydrocarbons. J. Phys. Chem. A 105, 9396–9409 (2001).

    Article  Google Scholar 

  39. Liang, T., Phillpot, S. R. & Sinnott, S. B. Parametrization of a reactive many-body potential for Mo–S systems. Phys. Rev. B Condens. Matter Mater. Phys. 79, 245110 (2009).

    Article  Google Scholar 

  40. Sun, H. COMPASS: an ab initio force-field optimized for condensed-phase applications—overview with details on alkane and benzene compounds. J. Phys. Chem. B 102, 7338–7364 (1998).

    Article  Google Scholar 

  41. Fonseca, A. F. et al. Graphene–titanium interfaces from molecular dynamics simulations. ACS Appl. Mater. Interfaces 9, 33288–33297 (2017).

    Article  Google Scholar 

  42. Xiong, S. & Cao, G. Bending response of single layer MoS2. Nanotechnology 27, 105701 (2016).

    Article  Google Scholar 

  43. Chen, H., Lu, B.-W., Lin, Y. & Feng, X. Interfacial failure in flexible electronic devices. IEEE Electron Device Lett. 35, 132–134 (2014).

    Article  Google Scholar 

  44. Bae, S. et al. Roll-to-roll production of 30-inch graphene films for transparent electrodes. Nat. Nanotechnol. 5, 574–578 (2010).

    Article  Google Scholar 

Download references

Acknowledgements

We acknowledge support from NSF (MRSEC DMR-1720633, ECCS-1935775, DMR-1708852 and CMMI-1554019), AFOSR (FA2386-17-1-4071), NASA ECF (NNX16AR56G), ONR YIP (N00014-17-1-2830) and LLNL (B622092). C.C. acknowledges support from a NASA Space Technology Research Fellow grant (80NSSC17K0149). The simulations were performed using the Extreme Science and Engineering Discovery Environment (XSEDE; supported by NSF grant no. OCI1053575), Blue Waters (supported by NSF awards OCI-0725070, ACI-1238993 and the State of Illinois, and, as of December 2019, by the National Geospatial-Intelligence Agency) and Frontera computing project at the Texas Advanced Computing Center (supported by NSF grant no. OAC-1818253). This research was primarily supported by the NSF through the University of Illinois at Urbana-Champaign Materials Research Science and Engineering Center (DMR-1720633). We are grateful for helpful discussions with A. J. Rosakis and J. A. Rogers.

Author information

Author notes

  1. These authors contributed equally: Chullhee Cho, Pilgyu Kang.

Authors and Affiliations

  1. Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA

    Chullhee Cho, Pilgyu Kang, Amir Taqieddin, Yuhang Jing, Keong Yong, Md Farhadul Haque, Narayana R. Aluru & SungWoo Nam

  2. Department of Mechanical Engineering, George Mason University, Fairfax, VA, USA

    Pilgyu Kang

  3. Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, USA

    Jin Myung Kim & SungWoo Nam

Authors
  1. Chullhee Cho
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Pilgyu Kang
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Amir Taqieddin
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Yuhang Jing
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Keong Yong
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Jin Myung Kim
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Md Farhadul Haque
    View author publications

    You can also search for this author in PubMed Google Scholar

  8. Narayana R. Aluru
    View author publications

    You can also search for this author in PubMed Google Scholar

  9. SungWoo Nam
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

C.C., P.K. and S.N. conceived the idea, designed experiments and contributed to the discussion and analysis of the results. C.C. performed fabrication and characterization, and wrote the manuscript. A.T., Y.J. and N.R.A. contributed to the analytical and computational analysis. K.Y. worked on the growth of 2D materials and assisted with twist and fatigue tests. J.M.K. worked on fracture monitor videos. M.F.H. performed atomic force microscopy characterizations.

Corresponding author

Correspondence to SungWoo Nam.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Peer review information Nature Electronics thanks Seung Hwan Ko and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary Figs. 1–23, Table 1, video captions 1–3 and Notes.

Supplementary Video 1

Crack development in a bare Au electrode under bending deformation.

Supplementary Video 2

Crack development in an Au/1LG electrode under bending deformation.

Supplementary Video 3

Practical functionality demonstration of flexible light-emitting devices integrated with a conventional thin-metal-film-based interconnector and a metal–2D-based interconnector.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Cho, C., Kang, P., Taqieddin, A. et al. Strain-resilient electrical functionality in thin-film metal electrodes using two-dimensional interlayers. Nat Electron 4, 126–133 (2021). https://doi.org/10.1038/s41928-021-00538-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/s41928-021-00538-4

Search

Advanced search

Quick links

Nature Briefing

Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily.

Get the most important science stories of the day, free in your inbox. Sign up for Nature Briefing