Graphene is a promising electrode material for supercapacitors mainly because of its large specific surface area and high conductivity. In practice, however, several fabrication issues need refinement. The restacking of graphene flakes upon being packed into supercapacitor electrodes has become a critical challenge in the full utilization of graphene’s large specific surface area to further improve the device performance. In this review, a variety of recent techniques and strategies are overviewed for the prevention of graphene restacking. They have been classified into several categories to improve and facilitate the discussion on the underlying ideas. Based on the overview of the existing techniques, we discuss the trends of future research in the fields.
References
[1]
Simon, P.; Gogotsi, Y. Materials for electrochemical capacitors. Nat. Mater. 2008, 7, 845–854, doi:10.1038/nmat2297.
[2]
Miller, J.R.; Simon, P. Electrochemical capacitors for energy management. Science 2008, 321, 651–652, doi:10.1126/science.1158736.
[3]
Conway, B.E. Electrochemical Supercapacitors: Scientific Fundamentals and Technological Applications; Kluwer Academic/Plenum: New York, NY, USA, 1999.
[4]
Chmiola, J.; Largeot, C.; Taberna, P.-L.; Simon, P.; Gogotsi, Y. Monolithic carbide-derived carbon films for micro-supercapacitors. Science 2010, 328, 480–483, doi:10.1126/science.1184126.
[5]
Geim, A.K.; Novoselov, K.S. The rise of graphene. Nat. Mater. 2007, 6, 183–191, doi:10.1038/nmat1849.
Luo, B.; Liu, S.; Zhi, L. Chemical approaches toward graphene-based nanomaterials and their applications in energy-related areas. Small 2012, 8, 630–646, doi:10.1002/smll.201101396.
[10]
Huang, Y.; Liang, J.; Chen, Y. An overview of the applications of graphene-based materials in supercapacitors. Small 2012, 8, 1805–1834, doi:10.1002/smll.201102635.
Jiang, H.; Lee, P.S.; Li, C. 3D carbon based nanostructures for advanced supercapacitors. Energy Environ. Sci. 2013, 6, 41–53, doi:10.1039/c2ee23284g.
[13]
Brownson, D.A.C.; Kampouris, D.K.; Banks, C.E. An overview of graphene in energy production and storage applications. J. Power Sources 2011, 196, 4873–4885, doi:10.1016/j.jpowsour.2011.02.022.
[14]
Grande, L.; Chundi, V.T.; Wei, D.; Bower, C.; Andrew, P.; Ryh？nen, T. Graphene for energy harvesting/storage devices and printed electronics. Particuology 2012, 10, 1–8, doi:10.1016/j.partic.2011.12.001.
[15]
Choi, H.-J.; Jung, S.-M.; Seo, J.-M.; Chang, D.W.; Dai, L.; Baek, J.-B. Graphene for energy conversion and storage in fuel cells and supercapacitors. Nano Energy 2012, 1, 534–551, doi:10.1016/j.nanoen.2012.05.001.
Liu, C.; Yu, Z.; Neff, D.; Zhamu, A.; Jang, B.Z. Graphene-based supercapacitor with an ultrahigh energy density. Nano Lett. 2010, 10, 4863–4868, doi:10.1021/nl102661q.
[24]
Liu, F.; Song, S.; Xue, D.; Zhang, H. Folded structured graphene paper for high performance electrode materials. Adv. Mater. 2012, 24, 1089–1094, doi:10.1002/adma.201104691.
[25]
Wen, Z.; Wang, X.; Mao, S.; Bo, Z.; Kim, H.; Cui, S.; Lu, G.; Feng, X.; Chen, J. Crumpled nitrogen-doped graphene nanosheets with ultrahigh pore volume for high-performance supercapacitor. Adv. Mater. 2012, 24, 5610–5616, doi:10.1002/adma.201201920.
Huang, Z.-D.; Zhang, B.; Oh, S.-W.; Zheng, Q.-B.; Lin, X.-Y.; Yousefi, N.; Kim, J.-K. Self-assembled reduced graphene oxide/carbon nanotube thin films as electrodes for supercapacitors. J. Mater. Chem. 2012, 22, 3591–3599.
[28]
Cheng, Q.; Tang, J.; Ma, J.; Zhang, H.; Shinya, N.; Qin, L.-C. Graphene and carbon nanotube composite electrodes for supercapacitors with ultra-high energy density. Phys. Chem. Chem. Phys. 2011, 13, 17615–17624.
[29]
Wang, Y.; Wu, Y.; Huang, Y.; Zhang, F.; Yang, X.; Ma, Y.; Chen, Y. Preventing graphene sheets from restacking for high-capacitance performance. J. Phys. Chem. C 2011, 115, 23192–23197.
[30]
Fan, Z.; Yan, J.; Zhi, L.; Zhang, Q.; Wei, T.; Feng, J.; Zhang, M.; Qian, W.; Wei, F. A three-dimensional carbon nanotube/graphene sandwich and its application as electrode in supercapacitors. Adv. Mater. 2010, 22, 3723–3728, doi:10.1002/adma.201001029.
[31]
Xu, Z.; Li, Z.; Holt, C.M. B.; Tan, X.; Wang, H.; Amirkhiz, B.S.; Stephenson, T.; Mitlin, D. Electrochemical supercapacitor electrodes from sponge-like graphene nanoarchitectures with ultrahigh power density. J. Phys. Chem. Lett. 2012, 3, 2928–2933.
[32]
Yang, X.; Zhu, J.; Qiu, L.; Li, D. Bioinspired effective prevention of restacking in multilayered graphene films: towards the next generation of high-performance supercapacitors. Adv. Mater. 2011, 23, 2833–2838, doi:10.1002/adma.201100261.
An, J.; Liu, J.; Zhou, Y.; Zhao, H.; Ma, Y.; Li, M.; Yu, M.; Li, S. Polyaniline-grafted graphene hybrid with amide groups and its use in supercapacitors. J. Phys. Chem. C 2012, 116, 19699–19708.
[35]
Wu, Q.; Xu, Y.; Yao, Z.; Liu, A.; Shi, G. Supercapacitors based on flexible graphene/polyaniline nanofiber composite films. ACS Nano 2010, 4, 1963–1970, doi:10.1021/nn1000035.
[36]
Xu, J.; Wang, K.; Zu, S.-Z.; Han, B.-H.; Wei, Z. Hierarchical nanocomposites of polyaniline nanowire arrays on graphene oxide sheets with synergistic effect for energy storage. ACS Nano 2010, 4, 5019–5026, doi:10.1021/nn1006539.
[37]
Zhang, J.; Zhao, X.S. Conducting polymers directly coated on reduced graphene oxide sheets as high-performance supercapacitor electrodes. J. Phys. Chem. C 2012, 116, 5420–5426, doi:10.1021/jp211474e.
Yu, G.; Hu, L.; Liu, N.; Wang, H.; Vosgueritchian, M.; Yang, Y.; Cui, Y.; Bao, Z. Enhancing the supercapacitor performance of graphene/MnO2 nanostructured electrodes by conductive wrapping. Nano Lett. 2011, 11, 4438–4442, doi:10.1021/nl2026635.
[41]
Yu, G.; Hu, L.; Vosgueritchian, M.; Wang, H.; Xie, X.; McDonough, J.R.; Cui, X.; Cui, Y.; Bao, Z. Solution-processed graphene/MnO2 nanostructured textiles for high-performance electrochemical capacitors. Nano Lett. 2011, 11, 2905–2911.
[42]
Cheng, Y.; Lu, S.; Zhang, H.; Varanasi, C. V; Liu, J. Synergistic effects from graphene and carbon nanotubes enable flexible and robust electrodes for high-performance supercapacitors. Nano Lett. 2012, 12, 4206–4211, doi:10.1021/nl301804c.
[43]
Du, F.; Yu, D.; Dai, L.; Ganguli, S.; Varshney, V.; Roy, A.K. Preparation of tunable 3D pillared carbon nanotube—Graphene networks for high-performance capacitance. Chem. Mater. 2011, 23, 4810–4816, doi:10.1021/cm2021214.
[44]
Yan, J.; Wei, T.; Fan, Z.; Qian, W.; Zhang, M.; Shen, X.; Wei, F. Preparation of graphene nanosheet/carbon nanotube/polyaniline composite as electrode material for supercapacitors. J. Power Sources 2010, 195, 3041–3045, doi:10.1016/j.jpowsour.2009.11.028.
[45]
Xu, Y.; Sheng, K.; Li, C.; Shi, G. Self-assembled graphene hydrogel via a one-step hydrothermal process. ACS Nano 2010, 4, 4324–4330, doi:10.1021/nn101187z.
Sheng, K.; Sun, Y.; Li, C.; Yuan, W.; Shi, G. Ultrahigh-rate supercapacitors based on eletrochemically reduced graphene oxide for ac line-filtering. Sci. Rep. 2012, 2, doi:10.1038/srep00247.
[51]
Li, J.; Ye, F.; Vaziri, S.; Muhammed, M.; Lemme, M.C.; ？stling, M. Efficient inkjet printing of graphene. Adv. Mater. 2013. submitted for publication.
[52]
Li, J.; Ye, F.; Vaziri, S.; Muhammed, M.; Lemme, M.C.; ？stling, M. A simple route towards high-concentration surfactant-free graphene dispersions. Carbon 2012, 50, 3113–3116, doi:10.1016/j.carbon.2012.03.011.
[53]
Gao, W.; Singh, N.; Song, L.; Liu, Z.; Reddy, A.L. M.; Ci, L.; Vajtai, R.; Zhang, Q.; Wei, B.; Ajayan, P.M. Direct laser writing of micro-supercapacitors on hydrated graphite oxide films. Nat. Nanotechnol. 2011, 6, 496–500, doi:10.1038/nnano.2011.110.
[54]
Chen, J.; Sheng, K.; Luo, P.; Li, C.; Shi, G. Graphene hydrogels deposited in nickel foams for high-rate electrochemical capacitors. Adv. Mater. 2012, 24, 4569–4573, doi:10.1002/adma.201201978.
[55]
Dong, X.-C.; Xu, H.; Wang, X.-W.; Huang, Y.-X.; Chan-Park, M.B.; Zhang, H.; Wang, L.-H.; Huang, W.; Chen, P. 3D graphene-cobalt oxide electrode for high-performance supercapacitor and enzymeless glucose detection. ACS Nano 2012, 6, 3206–3213.
