Graphene1, a two-dimensional honeycomb lattice of carbon atoms of great interest in (opto)electronics2,3 and plasmonics4,5,6,7,8,9,10,11, can be obtained by means of diverse fabrication techniques, among which chemical vapour deposition (CVD) is one of the most promising for technological applications12. The electronic and mechanical properties of CVD-grown graphene depend in large part on the characteristics of the grain boundaries13,14,15,16,17,18,19. However, the physical properties of these grain boundaries remain challenging to characterize directly and conveniently15,16,17,18,19,20,21,22,23. Here we show that it is possible to visualize and investigate the grain boundaries in CVD-grown graphene using an infrared nano-imaging technique. We harness surface plasmons that are reflected and scattered by the graphene grain boundaries, thus causing plasmon interference. By recording and analysing the interference patterns, we can map grain boundaries for a large-area CVD graphene film and probe the electronic properties of individual grain boundaries. Quantitative analysis reveals that grain boundaries form electronic barriers that obstruct both electrical transport and plasmon propagation. The effective width of these barriers (∼10–20 nm) depends on the electronic screening and is on the order of the Fermi wavelength of graphene. These results uncover a microscopic mechanism that is responsible for the low electron mobility observed in CVD-grown graphene, and suggest the possibility of using electronic barriers to realize tunable plasmon reflectors and phase retarders in future graphene-based plasmonic circuits.
Subscribe to Journal
Get full journal access for 1 year
only $15.58 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.
Geim, A. K. & Novoselov, K. S. The rise of graphene. Nature Mater. 6, 183–191 (2007).
Castro Neto, A. H., Guinea, F., Peres, N. M. R., Novoselov, K. S. & Geim, A. K. The electronic properties of graphene. Rev. Mod. Phys. 81, 109–162 (2009).
Bonaccorso, F., Sun, Z., Hasan, T. & Ferrari, A. C. Graphene photonics and optoelectronics. Nature Photon. 4, 611–622 (2010).
Vakil, A. & Engheta, N. Transformation optics using graphene. Science 332, 1291–1294 (2011).
Ju, L. et al. Graphene plasmonics for tunable terahertz metamaterials. Nature Nanotech. 6, 630–634 (2011).
Fei, Z. et al. Infrared nanoscopy of Dirac plasmons at the graphene–SiO2 interface. Nano Lett. 11, 4701–4705 (2011).
Fei, Z. et al. Gate-tuning of graphene plasmons revealed by infrared nano-imaging. Nature 487, 82–85 (2012).
Chen, J. et al. Optical nano-imaging of gate-tunable graphene plasmons. Nature 487, 77–81 (2012).
Yan, H. et al. Tunable infrared plasmonic devices using graphene/insulator stacks. Nature Nanotech. 7, 330–334 (2012).
Grigorenko, A. N., Polini, M. & Novoselov, K. S. Graphene plasmonics. Nature Photon. 6, 749–758 (2012).
Jablan, M., Buljan, H. & Slojačić, M. Plasmonics in graphene at infrared frequencies. Phys. Rev. B 80, 245435 (2009).
Li, X. et al. Large-area synthesis of high-quality and uniform graphene films on copper foils. Science 324, 1312–1314 (2009).
Grantab, R., Shenoy, V. B. & Ruoff, R. S. Anomalous strength characteristics of tilt grain boundaries in graphene. Science 330, 946–948 (2010).
Wei, Y. et al. The nature of strength enhancement and weakening by pentagon–heptagon defects in graphene. Nature Mater. 11, 759–763 (2012).
Yu, Q. et al. Control and characterization of individual grains and grain boundaries in graphene grown by chemical vapour deposition. Nature Mater. 10, 443–449 (2011).
Song, H. S. et al. Origin of the relatively low transport mobility of graphene grown through chemical vapor deposition. Sci. Rep. 2, 337 (2012).
Tsen, A. W. et al. Tailoring electrical transport across grain boundaries in polycrystalline graphene. Science 336, 1143–1146 (2012).
Koepke, J. C. et al. Atomic-scale evidence for potential barriers and strong carrier scattering at graphene grain boundaries: a scanning tunneling microscopy study. ACS Nano. 7, 75–86 (2013).
Tapasztó, L. et al. Mapping the electronic properties of individual graphene grain boundaries. Appl. Phys. Lett. 100, 053114 (2012).
Huang, P. Y. et al. Grains and grain boundaries in single-layer graphene atomic patchwork quilts. Nature 469, 389–392 (2011).
Kim, K. et al. Grain boundary mapping in polycrystalline graphene. ACS Nano 5, 2142–2146 (2011).
Duong, D. L. et al. Probing graphene grain boundaries with optical microscopy. Nature 490, 235–239 (2012).
Kim, D. W., Kim, Y. H., Jeong, H. S. & Jung, H. T. Direct visualization of large-area graphene domains and boundaries by optical birefringency. Nature Nanotech. 7, 29–34 (2011).
Atkin, J. M., Berweger, S., Jones, A. C. & Raschke, M. B. Nano-optical imaging and spectroscopy of order, phases, and domains in complex solids. Adv. Phys. 61, 745–842 (2012).
An, J. et al. Domain (grain) boundaries and evidence of ‘twinlike’ structures in chemically vapor deposited grown graphene. ACS Nano 5, 2433–2439 (2011).
Ryu, S. et al. Atmospheric oxygen binding and hole doping in deformed graphene on a SiO2 substrate. Nano Lett. 10, 4944–4951 (2010).
Das, A., Chakraborty, B. & Sood, A. K. Raman spectroscopy of graphene on different substrates and influence of defects. Bull. Mater. Sci. 31, 579–584 (2008).
Kim, D. C. et al. The structural and electrical evolution of graphene by oxygen plasma-induced disorder. Nanotechnology 20, 375703 (2009).
Radchenko, T. M., Shylau, A. A. & Zozoulenko, I. V. Effect of charged line defects on conductivity in graphene: numerical Kubo and analytical Boltzmann approaches. Phys. Rev. B 87, 195448 (2013).
Lu, Y-J. et al. Plasmonic nanolaser using epitaxially grown silver film. Science 337, 450–453 (2012).
The authors acknowledge support from the Office of Naval Research. The development of scanning plasmon interferometry is supported by the US Department of Energy Office of Basic Energy Sciences. G.D. and M.T. were supported by the National Aeronautics and Space Administration (grant no. NNX11AF24G). M.F. is supported by the University of California Office of the President and the National Science Foundation (PHY11-25915). A.H.C.N. acknowledges a Singapore National Research Foundation Competitive Research Programme grant (R-144-000-295-281). M.W. thanks the Alexander von Humboldt Foundation for financial support. R.H. acknowledges a European Research Council starting grant (no. 258461). A.S.M. is supported by a US Department of Energy Office of Science Graduate Fellowship.
F.K. and R.H. are cofounders of Neaspec, producer of the s-SNOM apparatus used in this study.
About this article
Cite this article
Fei, Z., Rodin, A., Gannett, W. et al. Electronic and plasmonic phenomena at graphene grain boundaries. Nature Nanotech 8, 821–825 (2013). https://doi.org/10.1038/nnano.2013.197
Advanced Optical Materials (2020)
Communications Materials (2020)
2D Materials (2019)
Nano Letters (2019)
Advanced Materials (2019)