Authors
Abstract
In this study, quantum capacitance of graphene-based electrodes is evaluated using Density Functional Theory (DFT) calculations. The obtained results showed that quantum capacitance of graphene-based supercapacitors could be significantly improved by existence of structural defects on the graphene sheets at sufficiently high concentrations because of creating impure states resulted from carbon p < /font>z orbitals involved in defect. In another section of calculations, quantum capacitance of functionalized graphene with –C6H4, is evaluated. The obtained results of calculations showed that functionalized graphene with this functional group have a very good capacitance in comparison with pristine graphene, especially at smaller voltages of less than -1.0 V or greater than 1.0 V. Hybrid configurations between structural defects and functional group of –C6H4 was also studied. In general, the results indicated that the combined configuration shows higher capacity than pristine graphene
Keywords
2. H I Becker, “Low voltage electrolytic capacitor” (1957).
3. S Sarangapani, B V Tilak and C Chen, J Electrochem Soc. 143 (1996) 3791.
4. Y Wang, Z Shi, Y Huang, Y Ma, C Wang and M Chen, et al., J Phys Chem C 113 (2009)13103.
5. L R Shiue, C S Cheng, J H Chang, L P Li, W T Lo, and K F Huang, “Supercapacitor with high energy density” (2004).
6. J L Kaschmitter, S T Mayer and R W Pekala, “Supercapacitors based on carbon foams” (1993).
7. L L Zhang, R Zhou and X S Zhao, J Mater Chem 20 (2010)5983.
8. A M Namisnyk, “A survey of electrochemical supercapacitor technology”, University of Technology, Sydney, (2003).
9. L L Zhang, X S Zhao, “Carbon-based materials as supercapacitor electrodes”, Royal Society of Chemistry, (2009).
10. K Milowska, M Birowska, and J Majewski Diam Relat Mater 23 (2012) 167.
11. Y Wang, H Sun, R Zhang, S Yu and J Kong. Carbon N Y 53 (2013) 245.
12. K Milowska, “Mechanical and Electrical Properties of Covalently Functionalized Carbon Nanotubes and Graphene Layers”, Department of Condensed Matter Physics, (2013).
13. P Plachinda, D Evans and R Solanki, Solid State Electron 79 (2013) 262. doi:10.1016/j. sse. (2012).08. 009.
14. Y Chen, X Zhang, D Zhang, P Yu and Y Ma, Carbon N Y 49 (2011) 573.
15. A Du Pasquier, I Plitz, S Menocal, and G Amatucci, J Power Sources 115 (2003) 171.
16. C D Lokhande, D P Dubal, and O-S Joo, Curr Appl Phys 11 (2011) 255.
17. E Frackowiak., Phys Chem Chem Phys 9 (2007) 1774.
18. E Paek, A J Pak, K E Kweon and G S Hwang., J Phys Chem C 117 (2013) 5610.
19. B E Conway, “Electrochemical supercapacitors”, New York: New york Kluwer Academic (1999).
20. H Y Lee, and J B Goodenough., J Solid State Chem 144 (1999) 220.
21. T Fang, A Konar, H Xing, D Jena., Appl Phys Lett 91 (2007) 92109.
22. E Paek, A J Pak, G S Hwang., J Electrochem Soc., 160 (2012) 1.
23. B C B Wood, T Ogitsu, M Otani, and J Biener, J Phys Chem C 118 (2013) 4.
24. D L John, L C Castro and D L Pulfrey., J Appl Phys 96 (2004) 5180.
25. S M Mousavi-Khoshdel, and E Targholi., Carbon 89 (2015) 148.
26. P Giannozzi, S Baroni, N Bonini, M Calandra, R Car, C Cavazzoni, et al., J Phys Condens Matter 21 (2009) 395502.
27. J P Perdew, K Burke and M Ernzerhof., Phys Rev Lett 77 (1996) 3865.
)