Measurement of the quantum capacitance of graphene
Source abstract
Abstract
Graphene has received widespread attention due to its unique electronic properties. Much of the research conducted so far has focused on electron mobility, which is determined by scattering from charged impurities and other inhomogeneities. However, another important quantity, the quantum capacitance, has been largely overlooked. Here, we report a direct measurement of the quantum capacitance of graphene as a function of gate potential using a three-electrode electrochemical configuration. The quantum capacitance has a non-zero minimum at the Dirac point and a linear increase on both sides of the minimum with relatively small slopes. Our findings -- which are not predicted by theory for ideal graphene -- suggest that charged impurities also influences the quantum capacitance. We also measured the capacitance in aqueous solutions at different ionic concentrations, and our results strongly indicate that the long-standing puzzle about the interfacial capacitance in carbon-based electrodes has a quantum origin.
Source: europepmc · Quality: candidate unverified · Source record ↗
Research context
OpenAlex topics: Graphene research and applications · Advancements in Battery Materials · Electrochemical Analysis and Applications
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
References (30)
Show source-provided references
1. Novoselov, K. S. et al. Two-dimensional gas of massless Dirac fermions in graphene. Nature 438, 197–200 (2005).10.1038/nature04233 ↗
2. Chen, J. H., Jang, C., Xiao, S. D., Ishigami, M. & Fuhrer, M. S. Intrinsic and extrinsic performance limits of graphene devices on SiO2 . Nature Nanotech. 3, 206–209 (2008).10.1038/nnano.2008.58 ↗
3. Geim, A. K. & Novoselov, K. S. The rise of graphene. Nature Mater. 6, 183–191 (2007).10.1038/nmat1849 ↗
4. Meric, I. et al. Current saturation in zero-bandgap, top-gated graphene field-effect transistors. Nature Nanotech. 3, 654–659 (2008).10.1038/nnano.2008.268 ↗
5. Schedin, F. et al. Detection of individual gas molecules adsorbed on graphene. Nature Mater. 6, 652–655 (2007).10.1038/nmat1967 ↗
6. Martin, J. et al. Observation of electron–hole puddles in graphene using a scanning single-electron transistor. Nature Phys. 4, 144–148 (2008).10.1038/nphys781 ↗
7. Das, A. et al. Monitoring dopants by Raman scattering in an electrochemically top-gated graphene transistor. Nature Nanotech. 3, 210–215 (2008).10.1038/nnano.2008.67 ↗
8. Tan, Y. W. et al. Measurement of scattering rate and minimum conductivity in graphene. Phys. Rev. Lett. 99, 246803 (2007).10.1103/PhysRevLett.99.246803 ↗
9. Trushin, M. & Schliemann, J. Minimum electrical and thermal conductivity of graphene: a quasiclassical approach. Phys. Rev. Lett. 99, 216602 (2007).10.1103/PhysRevLett.99.216602 ↗
10. Chen, Z. & Appenzeller, J. Mobility extraction and quantum capacitance impact in high performance graphene field-effect transistor devices. IEEE IEDM Tech. Digest 21.1, 509–512 (2008).
11. John, D. L., Castro, L. C. & Pulfrey, D. L. Quantum capacitance in nanoscale device modeling. J. Appl. Phys. 96, 5180–5184 (2004).10.1063/1.1803614 ↗
12. Fang, T., Konar, A., Xing, H. L. & Jena, D. Carrier statistics and quantum capacitance of graphene sheets and ribbons. Appl. Phys. Lett. 91, 092109 (2007).10.1063/1.2776887 ↗
13. Giannazzo, F., Sonde, S., Raineri, V. & Rimini, E. Screening length and quantum capacitance in graphene by scanning probe microscopy. Nano Lett. 9, 23–29 (2009).10.1021/nl801823n ↗
14. Ishigami, M., Chen, J. H., Cullen, W. G., Fuhrer, M. S. & Williams, E. D. Atomic structure of graphene on SiO2 . Nano Lett. 7, 1643–1648 (2007).10.1021/nl070613a ↗
15. Stolyarova, E. et al. High-resolution scanning tunneling microscopy imaging of mesoscopic graphene sheets on an insulating surface. Proc. Natl Acad. Sci. USA 104, 9209–9212 (2007).10.1073/pnas.0703337104 ↗
16. Baldelli, S. Surface structure at the ionic liquid-electrified metal interface. Acc. Chem. Res. 41, 421–431 (2008).10.1021/ar700185h ↗
17. Chen, J. H. et al. Charged-impurity scattering in graphene. Nature Phys. 4, 377–381 (2008).10.1038/nphys935 ↗
18. Adam, S., Hwang, E. H., Galitski, V. M. & Das Sarma, S. A self-consistent theory for graphene transport. Proc. Natl Acad. Sci. USA 104, 18392–18397 (2007).10.1073/pnas.0704772104 ↗
19. Victor, M. G., Shaffique, A. & Sarma, S. D. Statistics of random voltage fluctuations and the low-density residual conductivity of graphene. Phys. Rev. B 76, 245405 (2007).10.1103/PhysRevB.76.245405 ↗
20. Ando, T. Screening effect and impurity scattering in monolayer graphene. J. Phys. Soc. Jpn 75, 074716 (2006).10.1143/JPSJ.75.074716 ↗
21. Jang, C. et al. Tuning the effective fine structure constant in graphene: opposing effects of dielectric screening on short- and long-range potential scattering. Phys. Rev. Lett. 101, 146805 (2008).10.1103/PhysRevLett.101.146805 ↗
22. Cho, S. & Fuhrer, M. S. Charge transport and inhomogeneity near the minimum conductivity point in graphene. Phys. Rev. B 77, 081402 (2008).10.1103/PhysRevB.77.081402 ↗
23. Randin, J. P. & Yeager, E. Differential capacitance study of stress/annealed pyrolytic graphite electrodes. J. Electrochem. Soc. 118, 711–714 (1971).10.1149/1.2408151 ↗
24. Bockris, J. O. M. Modern Electrochemistry: An Introduction to an Interdisciplinary Area 1st edn (Plenum Press, 1970).10.1007/978-1-4615-7464-4 ↗
25. Randin, J. P. & Yeager, E. Differential capacitance study on basal plane of stress-annealed pyrolytic-graphite. J. Electroanal. Chem. 36, 257–276 (1972).10.1016/S0022-0728(72)80249-3 ↗
26. Chen, F., Xia, J. L. & Tao, N. J. Ionic screening of charged-impurity scattering in graphene. Nano Lett. 9, 1621–1625 (2009).10.1021/nl803922m ↗
27. Zhou, S. Y. et al. First direct observation of Dirac fermions in graphite. Nature Phys. 2, 595–599 (2006).10.1038/nphys393 ↗
28. http://www.semicorp.com .
29. Blake, P. et al. Making graphene visible. Appl. Phys. Lett. 91, 063124 (2007).10.1063/1.2768624 ↗
30. Gao, L. B., Ren, W. C., Li, F. & Cheng, H. M. Total color difference for rapid and accurate identification of graphene. ACS Nano 2, 1625–1633 (2008).10.1021/nn800307s ↗