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:

Non-oxidative intercalation and exfoliation of graphite by Brønsted acids

Nature Chemistry volume 6, pages 957–963 (2014)Cite this article

Subjects

Abstract

Graphite intercalation compounds are formed by inserting guest molecules or ions between sp2-bonded carbon layers. These compounds are interesting as synthetic metals and as precursors to graphene. For many decades it has been thought that graphite intercalation must involve host–guest charge transfer, resulting in partial oxidation, reduction or covalent modification of the graphene sheets. Here, we revisit this concept and show that graphite can be reversibly intercalated by non-oxidizing Brønsted acids (phosphoric, sulfuric, dichloroacetic and alkylsulfonic acids). The products are mixtures of graphite and first-stage intercalation compounds. X-ray photoelectron and vibrational spectra indicate that the graphene layers are not oxidized or reduced in the intercalation process. These observations are supported by density functional theory calculations, which indicate a dipolar interaction between the guest molecules and the polarizable graphene sheets. The intercalated graphites readily exfoliate in dimethylformamide to give suspensions of crystalline single- and few-layer graphene sheets.

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

Figure 1: X-ray diffraction data from dried cryo-milled graphite (CMG)/acid films showing the progress of the intercalation reactions.
Figure 2: Edge-on electron microscopy images showing the expansion of graphite particles upon intercalation.
Figure 3: XPS spectra show only small changes in electron density in the sp2-bonded carbon sheets upon intercalation with acids.
Figure 4: Exfoliation of graphite is assisted by acid intercalation.
Figure 5: Most energetically favourable structures of phosphoric acid-intercalated graphite from DFT calculations, showing the direct interaction of acidic OH hydrogen atoms with the carbon sheets.
Figure 6: Differential charge density map of H3PO4-intercalated graphite and boron nitride.

Similar content being viewed by others

References

  1. Schafhäutl, C. Ueber die Verbindungen des Kohlenstoffes mit Silicium, Eisen, and anderen Metallen, welche die verschiedenen Gattungen von Roheisen, Stahl und Schmiedeeisen bilden. J. Prakt. Chem. 21, 129–157 (1840).

    Article  Google Scholar 

  2. Brodie, M. B-C. Note sur un nouveau procédé pour la purification et la désagrégation du graphite. Ann. Chim. Phys. 45, 351–353 (1855).

    Google Scholar 

  3. Dresselhaus, M. S. & Dresselhaus, G. Intercalation compounds of graphite. Adv. Phys. 51, 1–186 (2002).

    Article  CAS  Google Scholar 

  4. Levy, F. (ed.) Intercalated Layered Materials (D. Reidel, 1979).

    Book  Google Scholar 

  5. Moissette, A. et al. Spontaneous intercalation of sulfuric acid into graphite and synthesis of a new graphite–uranyl sulfate compound. Mater. Sci. Forum 91–93, 95–99 (1992).

    Article  Google Scholar 

  6. Hofmann, U. & Rüdorff, W. The formation of salts from graphite by strong acids. Trans. Faraday Soc. 38, 1017–1021 (1938).

    Article  Google Scholar 

  7. Schollhorn, R. Reversible topotactic redox reactions of solids by electron-ion transfer. Angew. Chem. Int. Ed. Engl. 19, 983–1003 (1980).

    Article  Google Scholar 

  8. Bartlett, N. et al. Oxidative intercalation of graphite by fluoroanionic species—evidence for thermodynamic barrier. Adv. Chem. Ser. 226, 391–402 (1990).

    Article  Google Scholar 

  9. Lerf, A., He, H., Forster, M. & Klinowski, J. Structure of graphite oxide revisited. J. Phys. Chem. B 102, 4477–4482 (1998).

    Article  CAS  Google Scholar 

  10. Worsley, K. A. et al. Soluble graphene derived from graphite fluoride. Chem. Phys. Lett. 445, 51–56 (2007).

    Article  CAS  Google Scholar 

  11. Zhu, Y. et al. Graphene and graphene oxide: synthesis, properties, and applications. Adv. Mater. 22, 3906–3924 (2010).

    Article  CAS  Google Scholar 

  12. Viculis, L. M., Mack, J. J. & Kaner, R. B. A chemical route to carbon nanoscrolls. Science 299, 1361 (2003).

    Article  CAS  Google Scholar 

  13. Zhang, Z. W. & Lerner, M. M. Preparation, characterization, and exfoliation of graphite perfluorooctanesulfonate. Chem. Mater. 8, 257–263 (1996).

    Article  CAS  Google Scholar 

  14. Nicolosi, V., Chhowalla, M., Kanatzidis, M. G., Strano, M. S. & Coleman, J. N. Liquid exfoliation of layered materials. Science 340, 1420 (2013).

    Article  CAS  Google Scholar 

  15. Kovtyukhova, N. I. et al. Reversible intercalation of hexagonal boron nitride with Brønsted acids. J. Am. Chem. Soc. 135, 8372–8381 (2013).

    Article  CAS  Google Scholar 

  16. Shen, C. P. et al. Intercalation of hexagonal boron nitride by strong oxidizers and evidence for the metallic nature of the products. J. Solid State Chem. 147, 74–81 (1999).

    Article  CAS  Google Scholar 

  17. Cullity, B. D. Elements of X-Ray Diffraction 284–285 (Addison-Wesley, 1978).

    Google Scholar 

  18. Bottomley, M., Parry, G., Ubbelohde, A. & Young, D. Electrochemical preparation of salts from well-oriented graphite. J. Chem. Soc. 5674–5680 (1963).

  19. Hooley, J. S. Isotherms of metal chloride vapors on graphite. Carbon 11, 225–236 (1973).

    Article  CAS  Google Scholar 

  20. Carr, K. E. Intercalation and oxidation effects on graphite of a mixture of sulphuric and nitric acids. Carbon 8, 155–166 (1970).

    Article  CAS  Google Scholar 

  21. McKelvy, M. & Glaunsinger, W. Molecular intercalation reactions in lamellar compounds. Annu. Rev. Phys. Chem. 41, 497–523 (1990).

    Article  CAS  Google Scholar 

  22. Wang, C., McKelvy, M. & Glaunsinger, W. Early events in intercalation reactions: the preintercalation state. J. Phys. Chem. 100, 19218–19222 (1996).

    Article  CAS  Google Scholar 

  23. Butler, S. Z. et al. Progress, challenges, and opportunities in two-dimensional materials beyond graphene. ACS Nano 4, 2898–2926 (2013).

    Article  Google Scholar 

  24. Muchharia, B. et al. Tunable electronics in large-area atomic layers of boron–nitrogen–carbon. Nano Lett. 13, 3476–3481 (2013).

    Article  Google Scholar 

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

    Article  CAS  Google Scholar 

Download references

Acknowledgements

Electron and atomic force microscopy, FTIR and XPS were conducted at the Materials Characterization Laboratory of the Pennsylvania State University. The authors thank T. Clark and V. Bojan for help with TEM and XPS analysis and A. van Duin for help in developing the ReaxFF parameterization for modelling of the H3PO4/graphite system. This work is supported by US Army Research Office MURI grant W911NF-11-1-0362.

Author information

Authors and Affiliations

  1. Department of Chemistry, The Pennsylvania State University, University Park, 16802, Pennsylvania, USA

    Nina I. Kovtyukhova & Thomas E. Mallouk

  2. Department of Physics, The Pennsylvania State University, University Park, 16802, Pennsylvania, USA

    Yuanxi Wang, Ayse Berkdemir, Mauricio Terrones, Vincent H. Crespi & Thomas E. Mallouk

  3. Department of Biochemistry and Molecular Biology, The Pennsylvania State University, University Park, 16802, Pennsylvania, USA

    Thomas E. Mallouk

  4. Research Center for Exotic Nanocarbons, Shinshu University, 4-17-1 Wakasato, Nagano, 380-8553, Japan

    Rodolfo Cruz-Silva

Authors
  1. Nina I. Kovtyukhova
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Yuanxi Wang
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Ayse Berkdemir
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Rodolfo Cruz-Silva
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Mauricio Terrones
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Vincent H. Crespi
    View author publications

    You can also search for this author in PubMed Google Scholar

  7. Thomas E. Mallouk
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

N.I.K. designed and performed the experiments. Y.W. performed computer simulations. A.B. collected Raman spectra. R.C. prepared CMG. T.E.M., V.H.C., M.T., Y.W. and N.I.K. supervised the research and contributed to the interpretation of data and writing of the paper.

Corresponding author

Correspondence to Thomas E. Mallouk.

Ethics declarations

Competing interests

The authors declare no competing financial interests.

Supplementary information

Supplementary information

Supplementary information (PDF 4366 kb)

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Kovtyukhova, N., Wang, Y., Berkdemir, A. et al. Non-oxidative intercalation and exfoliation of graphite by Brønsted acids. Nature Chem 6, 957–963 (2014). https://doi.org/10.1038/nchem.2054

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1038/nchem.2054

This article is cited by

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