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.

Single-crystal, large-area, fold-free monolayer graphene

Abstract

Chemical vapour deposition of carbon-containing precursors on metal substrates is currently the most promising route for the scalable synthesis of large-area, high-quality graphene films1. However, there are usually some imperfections present in the resulting films: grain boundaries, regions with additional layers (adlayers), and wrinkles or folds, all of which can degrade the performance of graphene in various applications2,3,4,5,6,7. There have been numerous studies on ways to eliminate grain boundaries8,9 and adlayers10,11,12, but graphene folds have been less investigated. Here we explore the wrinkling/folding process for graphene films grown from an ethylene precursor on single-crystal Cu–Ni(111) foils. We identify a critical growth temperature (1,030 kelvin) above which folds will naturally form during the subsequent cooling process. Specifically, the compressive stress that builds up owing to thermal contraction during cooling is released by the abrupt onset of step bunching in the foil at about 1,030 kelvin, triggering the formation of graphene folds perpendicular to the step edge direction. By restricting the initial growth temperature to between 1,000 kelvin and 1,030 kelvin, we can produce large areas of single-crystal monolayer graphene films that are high-quality and fold-free. The resulting films show highly uniform transport properties: field-effect transistors prepared from these films exhibit average room-temperature carrier mobilities of around (7.0 ± 1.0) × 103 centimetres squared per volt per second for both holes and electrons. The process is also scalable, permitting simultaneous growth of graphene of the same quality on multiple foils stacked in parallel. After electrochemical transfer of the graphene films from the foils, the foils themselves can be reused essentially indefinitely for further graphene growth.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: Investigation of the mechanism of graphene fold formation by cycling experiments.
Fig. 2: Fold evolution as a function of growth temperature.
Fig. 3: Characterizations of the fold-free graphene films.
Fig. 4: Transport properties of the fold-free graphene films.

Data availability

The data sets generated during the current study, and/or analysed during the current study, are available from the corresponding author upon reasonable request.

References

  1. 1.

    Li, X. et al. Large-area synthesis of high-quality and uniform graphene films on copper foils. Science 324, 1312–1314 (2009).

    ADS  CAS  Article  Google Scholar 

  2. 2.

    Zhu, W. et al. Structure and electronic transport in graphene wrinkles. Nano Lett. 12, 3431–3436 (2012).

    ADS  CAS  Article  Google Scholar 

  3. 3.

    Wang, B. et al. Camphor-enabled transfer and mechanical testing of centimeter-scale ultrathin films. Adv. Mater. 30, 1800888 (2018).

    Article  Google Scholar 

  4. 4.

    Huang, M. et al. Highly oriented monolayer graphene grown on a Cu/Ni(111) alloy foil. ACS Nano 12, 6117–6127 (2018).

    CAS  Article  Google Scholar 

  5. 5.

    Chen, S. et al. Thermal conductivity measurements of suspended graphene with and without wrinkles by micro-Raman mapping. Nanotechnology 23, 365701 (2012).

    ADS  Article  Google Scholar 

  6. 6.

    Li, X., Colombo, L. & Ruoff, R. S. Synthesis of graphene films on copper foils by chemical vapor deposition. Adv. Mater. 28, 6247–6252 (2016).

    CAS  Article  Google Scholar 

  7. 7.

    Luo, D. et al. Adlayer-free large-area single crystal graphene grown on a Cu(111) foil. Adv. Mater. 31, 1903615 (2019).

    Article  Google Scholar 

  8. 8.

    Wang, M., Luo, D., Wang, B. & Ruoff, R. S. Synthesis of large-area single-crystal graphene. Trends Chem. 3, 15–33 (2021).

    CAS  Article  Google Scholar 

  9. 9.

    Zhang, J. et al. Controlled growth of single-crystal graphene films. Adv. Mater. 32, 1903266 (2020).

    CAS  Article  Google Scholar 

  10. 10.

    Pang, J. et al. Oxidation as a means to remove surface contaminants on Cu foil prior to graphene growth by chemical vapor deposition. J. Phys. Chem. C 119, 13363–13368 (2015).

    Article  Google Scholar 

  11. 11.

    Han, Z. et al. Homogeneous optical and electronic properties of graphene due to the suppression of multilayer patches during CVD on copper foils. Adv. Funct. Mater. 24, 964–970 (2014).

    CAS  Article  Google Scholar 

  12. 12.

    Han, G. H. et al. Influence of copper morphology in forming nucleation seeds for graphene growth. Nano Lett. 11, 4144–4148 (2011).

    ADS  CAS  Article  Google Scholar 

  13. 13.

    Zhang, Y. et al. Defect-like structures of graphene on copper foils for strain relief investigated by high-resolution scanning tunneling microscopy. ACS Nano 5, 4014–4022 (2011).

    CAS  Article  Google Scholar 

  14. 14.

    Wang, W., Yang, S. & Wang, A. Observation of the unexpected morphology of graphene wrinkle on copper substrate. Sci. Rep. 7, 8244 (2017).

    ADS  Article  Google Scholar 

  15. 15.

    Tripathi, M. et al. Structural defects modulate electronic and nanomechanical properties of 2D materials. ACS Nano 15, 2520–2531 (2021).

    CAS  Article  Google Scholar 

  16. 16.

    Hattab, H. et al. Interplay of wrinkles, strain, and lattice parameter in graphene on iridium. Nano Lett. 12, 678–682 (2012).

    ADS  CAS  Article  Google Scholar 

  17. 17.

    Lee, J.-H. et al. Wafer-scale growth of single-crystal monolayer graphene on reusable hydrogen-terminated germanium. Science 344, 286–289 (2014).

    ADS  CAS  Article  Google Scholar 

  18. 18.

    Choi, J.-K. et al. Growth of wrinkle-free graphene on texture-controlled platinum films and thermal-assisted transfer of large-scale patterned graphene. ACS Nano 9, 679–686 (2015).

    CAS  Article  Google Scholar 

  19. 19.

    Zhang, X. et al. Epitaxial growth of 6 in. single-crystalline graphene on a Cu/Ni (111) film at 750 °C via chemical vapor deposition. Small 15, 1805395 (2019).

    Article  Google Scholar 

  20. 20.

    Deng, B. et al. Wrinkle-free single-crystal graphene wafer grown on strain-engineered substrates. ACS Nano 11, 12337–12345 (2017).

    CAS  Article  Google Scholar 

  21. 21.

    Zhang, Y. et al. Batch production of uniform graphene films via controlling gas-phase dynamics in confined space. Nanotechnology 32, 105603 (2021).

    ADS  CAS  Article  Google Scholar 

  22. 22.

    Polsen, E. S., McNerny, D. Q., Viswanath, B., Pattinson, S. W. & John Hart, A. High-speed roll-to-roll manufacturing of graphene using a concentric tube CVD reactor. Sci. Rep. 5, 10257 (2015).

    ADS  Article  Google Scholar 

  23. 23.

    Wang, Y. et al. Electrochemical delamination of CVD-grown graphene film: toward the recyclable use of copper catalyst. ACS Nano 5, 9927–9933 (2011).

    CAS  Article  Google Scholar 

  24. 24.

    Deng, B. et al. Anisotropic strain relaxation of graphene by corrugation on copper crystal surfaces. Small 14, 1800725 (2018).

    Article  Google Scholar 

  25. 25.

    Kang, J. H. et al. Strain relaxation of graphene layers by Cu surface roughening. Nano Lett. 16, 5993–5998 (2016).

    ADS  CAS  Article  Google Scholar 

  26. 26.

    Suh, I.-K., Ohta, H. & Waseda, Y. High-temperature thermal expansion of six metallic elements measured by dilatation method and X-ray diffraction. J. Mater. Sci. 23, 757–760 (1988).

    ADS  CAS  Article  Google Scholar 

  27. 27.

    Ferrari, A. C. et al. Raman spectrum of graphene and graphene layers. Phys. Rev. Lett. 97, 187401 (2006).

    ADS  CAS  Article  Google Scholar 

  28. 28.

    Lee, J. E., Ahn, G., Shim, J., Lee, Y. S. & Ryu, S. Optical separation of mechanical strain from charge doping in graphene. Nat. Commun. 3, 1024 (2012).

    ADS  Article  Google Scholar 

  29. 29.

    Zabel, J. et al. Raman spectroscopy of graphene and bilayer under biaxial strain: bubbles and balloons. Nano Lett. 12, 617–621 (2012).

    ADS  CAS  Article  Google Scholar 

  30. 30.

    Lee, G.-H. et al. High-strength chemical-vapor–deposited graphene and grain boundaries. Science 340, 1073–1076 (2013).

    ADS  CAS  Article  Google Scholar 

  31. 31.

    Yi, D. et al. What drives metal-surface step bunching in graphene chemical vapor deposition? Phys. Rev. Lett. 120, 246101 (2018).

    ADS  CAS  Article  Google Scholar 

  32. 32.

    Leong, W. S. et al. Paraffin-enabled graphene transfer. Nat. Commun. 10, 867 (2019).

    ADS  Article  Google Scholar 

  33. 33.

    Huang, M. et al. Large-area single-crystal AB-bilayer and ABA-trilayer graphene grown on a Cu/Ni(111) foil. Nat. Nanotechnol. 15, 289–295 (2020).

    ADS  CAS  Article  Google Scholar 

  34. 34.

    Kim, S. et al. Realization of a high mobility dual-gated graphene field-effect transistor with Al2O3 dielectric. Appl. Phys. Lett. 94, 062107 (2009).

    ADS  Article  Google Scholar 

  35. 35.

    Jin, S. et al. Colossal grain growth yields single-crystal metal foils by contact-free annealing. Science 362, 1021 (2018).

    ADS  CAS  Article  Google Scholar 

Download references

Acknowledgements

This work was supported by the Institute for Basic Science (IBS-R019-D1). We appreciate discussions with R. Huang (UT Austin) and K. Duck Park and H. Lee of UNIST.

Author information

Affiliations

Authors

Contributions

R.S.R., D.L. and Meihui Wang conceived the experiments. R.S.R. supervised the project. Meihui Wang did CVD growths. Meihui Wang and D.L. characterized films. S.J., Y.K. and M.K. prepared Cu(111) foils. M.H. and Mengran Wang prepared Cu–Ni(111) alloy foils. Y.L. made and tested the GFET devices. M.C., S.C. and Z.L. acquired and analysed TEM/SAED data. W.S. measured the LEED patterns and analysed the high-temperature XRD data (acquired by staff member M. J. Woo of the Korea Advanced Institute of Science and Technology (KAIST)). W.S. designed, built and tested the 6-inch CVD system which is now used by Meihui Wang and others. Meihui Wang wrote a draft manuscript and R.S.R., Meihui Wang and D.L. revised it. All co-authors commented on the manuscript prior to its submission.

Corresponding authors

Correspondence to Da Luo or Rodney S. Ruoff.

Ethics declarations

Competing interests

The Institute for Basic Science has filed a patent application (KR 10-2021-0095514) that lists Meihui Wang, D.L. and R.S.R. as inventors. Other than this, the authors declare no competing interests.

Additional information

Peer review information Nature thanks Cedric Huyghebaert, Jeehwan Kim and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.

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

Supplementary information

Supplementary Information

This file contains supplementary text, supplementary notes, supplementary figures s1 – s29, supplementary equations, supplementary tables s1 – s5 and supplementary references.

Peer Review File

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Wang, M., Huang, M., Luo, D. et al. Single-crystal, large-area, fold-free monolayer graphene. Nature 596, 519–524 (2021). https://doi.org/10.1038/s41586-021-03753-3

Download citation

Comments

By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.

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