The properties of polycrystalline materials are often dominated by the size of their grains and by the atomic structure of their grain boundaries. These effects should be especially pronounced in two-dimensional materials, where even a line defect can divide and disrupt a crystal. These issues take on practical significance in graphene, which is a hexagonal, two-dimensional crystal of carbon atoms. Single-atom-thick graphene sheets can now be produced by chemical vapour deposition1,2,3 on scales of up to metres4, making their polycrystallinity almost unavoidable. Theoretically, graphene grain boundaries are predicted to have distinct electronic5,6,7,8, magnetic9, chemical10 and mechanical11,12,13 properties that strongly depend on their atomic arrangement. Yet because of the five-order-of-magnitude size difference between grains and the atoms at grain boundaries, few experiments have fully explored the graphene grain structure. Here we use a combination of old and new transmission electron microscopy techniques to bridge these length scales. Using atomic-resolution imaging, we determine the location and identity of every atom at a grain boundary and find that different grains stitch together predominantly through pentagon–heptagon pairs. Rather than individually imaging the several billion atoms in each grain, we use diffraction-filtered imaging14 to rapidly map the location, orientation and shape of several hundred grains and boundaries, where only a handful have been previously reported15,16,17,18,19. The resulting images reveal an unexpectedly small and intricate patchwork of grains connected by tilt boundaries. By correlating grain imaging with scanning probe and transport measurements, we show that these grain boundaries severely weaken the mechanical strength of graphene membranes but do not as drastically alter their electrical properties. These techniques open a new window for studies on the structure, properties and control of grains and grain boundaries in graphene and other two-dimensional materials.
Subscribe to Journal
Get full journal access for 1 year
only $3.90 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Rent or Buy article
Get time limited or full article access on ReadCube.
All prices are NET prices.
Li, X. et al. Large-area synthesis of high-quality and uniform graphene films on copper foils. Science 324, 1312–1314 (2009)
Reina, A. et al. Large area, few-layer graphene films on arbitrary substrates by chemical vapor deposition. Nano Lett. 9, 30–35 (2009)
Li, X. et al. Graphene films with large domain size by a two-step chemical vapor deposition process. Nano Lett. 10, 4328–4334 (2010)
Bae, S. et al. Roll-to-roll production of 30-inch graphene films for transparent electrodes. Nature Nanotechnol. 5, 574–578 (2010)
Cervenka, J. & Flipse, C. F. J. Structural and electronic properties of grain boundaries in graphite: planes of periodically distributed point defects. Phys. Rev. B 79, 195429 (2009)
Peres, N. M. R., Guinea, F. & Castro-Neto, A. H. Electronic properties of disordered two-dimensional carbon. Phys. Rev. B 73, 125411 (2006)
Yazyev, O. V. & Louie, S. G. Electronic transport in polycrystalline graphene. Nature Mater. 6, 806–809 (2010)
Mesaros, A., Papanikolaou, S., Flipse, C. F. J., Sadri, D. & Zaanen, J. Electronic states of graphene grain boundaries. Phys. Rev. B 82, 205119 (2010)
Cervenka, J., Katsnelson, M. I. & Flipse, C. F. J. Room-temperature ferromagnetism in graphite driven by two-dimensional networks of point defects. Nature Phys. 5, 840–844 (2009)
Malola, S., Hakkinen, H. & Koskinen, P. Structural, chemical, and dynamical trends in graphene grain boundaries. Phys. Rev. B 81, 165447 (2010)
Liu, Y. & Yakobson, B. I. Cones, pringles, and grain boundary landscapes in graphene topology. Nano Lett. 10, 2178–2183 (2010)
Grantab, R., Shenoy, V. B. & Ruoff, R. S. Anomalous strength characteristics of tilt grain boundaries in graphene. Science 330, 946–948 (2010)
Yazyev, O. V. & Louie, S. G. Topological defects in graphene: dislocations and grain boundaries. Phys. Rev. B 81, 195420 (2010)
Hirsch, P., Howie, A., Nicholson, R., Pashley, D. W. & Whelan, M. J. Electron Microscopy of Thin Crystals (Krieger, 1965)
Zhao, L. et al. The atomic-scale growth of large-area monolayer graphene on single-crystal copper substrates. Preprint at 〈http://arxiv.org/abs/1008.3542〉 (2010)
Gao, L., Guest, J. R. & Guisinger, N. P. Epitaxial graphene on Cu(111). Nano Lett. 10, 3512–3516 (2010)
Cockayne, E. et al. Rotational grain boundaries in graphene. Preprint at 〈http://arxiv.org/abs/1008.3574〉 (2010)
Wofford, J. M., Nie, S., McCarty, K. F., Bartlet, N. C. & Dubon, O. D. Graphene islands on Cu foils: the interplay between shape, orientation, and defects. Nano Lett. 10, 4890–4896 (2010)
Park, H. J., Meyer, J., Roth, S. & Skakalova, V. Growth and properties of few-layer graphene prepared by chemical vapor deposition. Carbon 48, 1088–1094 (2010)
Regan, W. et al. A direct transfer of layer-area graphene. Appl. Phys. Lett. 96, 113102 (2010)
Krivanek, O. L. et al. Atom-by-atom structural and chemical analysis by annular dark-field electron microscopy. Nature 464, 571–574 (2010)
Hashimoto, A., Suenaga, K., Gloter, A., Urita, K. & Iijima, S. Direct evidence for atomic defects in graphene layers. Nature 430, 870–873 (2004)
Meyer, J. C. et al. Direct imaging of lattice atoms and topological defects in graphene membranes. Nano Lett. 8, 3582–3586 (2008)
de Villeneuve, V. W. A. et al. Hard sphere crystal nucleation and growth near large spherical impurities. J. Phys. Condens. Matter 17, S3371–S3378 (2005)
Park, S., Floresca, H. C., Suh, Y. & Kim, M. J. Electron microscopy analyses of natural and highly oriented pyrolytic graphites and the mechanically exfoliated graphenes produced from them. Carbon 48, 797–804 (2010)
Lee, C., Wei, X., Kysar, J. W. & Hone, J. Measurement of the elastic properties and intrinsic strength of monolayer graphene. Science 321, 385–388 (2008)
Geim, A. K. & Novoselov, K. S. The rise of graphene. Nature Mater. 6, 183–191 (2007)
Bachtold, A. et al. Scanned probe microscopy of electronic transport in carbon nanotubes. Phys. Rev. Lett. 84, 6082–6085 (2000)
Van Der Zande, A. M. et al. Large-scale arrays of single-layer graphene resonators. Nano Lett. 10, 4869–4873 (2010)
Thiel, S. et al. Electron scattering at dislocations in LaAlO3/SrTiO3 interfaces. Phys. Rev. Lett. 102, 046809 (2009)
Meyer, J. C., Chuvilin, A. & Kaiser, U. in MC2009, Vol. 3: Materials Science (eds Grogger, W., Hofer, F. & Polt, P. ) 347–348 (Graz Univ. Technology, 2009)
Suenaga, K. et al. Imaging active topological defects in carbon nanotubes. Nature Nanotechnol. 2, 358–360 (2007)
Jiao, L. et al. Creation of nanostructures with poly(methyl methacrylate)-mediated nanotransfer printing. J. Am. Chem. Soc. 130, 12612–12613 (2008)
The authors acknowledge discussions with M. Blees, J. Cha, S. Gerbode, J. Grazul, E. Kirkland, L. Fitting-Kourkoutis, O. Krivanek, S. Shi, S. Wang and H. Zhuang. This work was supported in part by the National Science Foundation through the Cornell Center for Materials Research and the Nanoscale Science and Engineering Initiative of the National Science Foundation under NSF Award EEC-0117770, 064654. Additional support was provided by the Army Research Office, CONACYT-Mexico, the Air Force Office of Scientific Research, DARPA-MTO and the MARCO Focused Research Center on Materials, Structures, and Devices. Sample fabrication was performed at the Cornell node of the National Nanofabrication Infrastructure Network, funded by the NSF. Additional facilities support was provided by the Cornell Center for Materials Research (NSF DMR-0520404 and IMR-0417392) and NYSTAR.
The authors declare no competing financial interests.
About this article
Cite this article
Huang, P., Ruiz-Vargas, C., van der Zande, A. et al. Grains and grain boundaries in single-layer graphene atomic patchwork quilts. Nature 469, 389–392 (2011). https://doi.org/10.1038/nature09718
The transition from an inverse pseudo Hall-Petch to a pseudo Hall-Petch behavior in nanocrystalline graphene
Journal of Applied Physics (2020)
Advanced Functional Materials (2020)
Nature Communications (2020)
Scientific Reports (2020)