Skip to main content
Log in

A new regularity used to predict the camel-bell shape transition in the capacitance curve of electric double layer capacitors

  • Research Article
  • Published:
Journal of Applied Electrochemistry Aims and scope Submit manuscript

Abstract

The concentration at which the camel-bell shape transition occurs in the capacitance curve of electric double layer capacitors is predicted via a new regularity stating that various plots of the integral capacitance, related to different surface charge densities, versus concentration (i.e., \({C}_{s}-C\) curves) intersect at a specific concentration. Interestingly, the concentration at the intersection point is found to correspond to that of the concentration of camel-bell shape transition. The existence of such intersection reveals that integral capacitance increases (decreases) with surface charge density for concentrations smaller (or, larger) than that corresponding to the intersection point. Using the modified fundamental measure theory within the framework of the restricted primitive model, this study explores the effects of wall curvature and its convexity or concavity on this regularity and the characteristics of the intersection point. Results show that the intersection point for a convex wall occurs at concentrations larger than those observed for concave walls. The new regularity described is found valid for the capacitance of electric double layers at the interface with walls of different curvatures, including the convex wall of a charged spherical colloid particle and concave wall of a charged spherical cavity as well as planar and cylindrical pores. Furthermore, it is shown that the regularity in question can be used to predict the concentration at which the observed minimum in the asymmetric capacitance curve disappears in the case of asymmetric electrolytes.

Graphic abstract

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Fig. 1
Fig. 2

adapted from Ref. [33] and the solid lines represent DFT calculations

Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8

Similar content being viewed by others

References

  1. Wang F, Wu X, Yuan X, Liu Z, Zhang Y, Fu L, Zhu Y, Zhou Q, Wu Y, Huang W (2017) Latest advances in supercapacitors: from new electrode materials to novel device designs. Chem Soc Rev 46(22):6816–6854

    Article  CAS  Google Scholar 

  2. Zhan C, Lian C, Zhang Y, Thompson MW, Xie Y, Wu J, Kent PR, Cummings PT, De J, Wesolowski DJ (2017) Computational insights into materials and interfaces for capacitive energy storage. Adv Sci 4(7):1700059

    Article  Google Scholar 

  3. Wang X, Mehandzhiyski AY, Arstad B, Van Aken KL, Mathis TS, Gallegos A, Tian Z, Ren D, Sheridan E, Grimes BA (2017) Selective charging behavior in an ionic mixture electrolyte-supercapacitor system for higher energy and power. J Am Chem Soc 139(51):18681–18687

    Article  CAS  Google Scholar 

  4. Kong X, Wu J, Henderson D (2015) Density functional theory study of the capacitance of single file ions in a narrow cylinder. J Colloid Interface Sci 449:130–135

    Article  CAS  Google Scholar 

  5. Henderson D, Lamperski S (2011) Simple description of the capacitance of the double layer of a high concentration electrolyte. J Chem Eng Data 56(4):1204–1208

    Article  CAS  Google Scholar 

  6. Lamperski S, Henderson D (2011) Simulation study of capacitance of the electrical double layer of an electrolyte near a highly charged electrode. Mol Simul 37(4):264–268

    Article  CAS  Google Scholar 

  7. Henderson D, Lamperski S, Jin Z, Wu J (2011) Density functional study of the electric double layer formed by a high density electrolyte. J Phys Chem B 115(44):12911–12914

    Article  CAS  Google Scholar 

  8. Jiang D-e, Meng D, Wu J (2011) Density functional theory for differential capacitance of planar electric double layers in ionic liquids. Chem Phys Lett 504(4–6):153–158

    Article  CAS  Google Scholar 

  9. Jiang De, Wu J (2013) Microscopic insights into the electrochemical behavior of nonaqueous electrolytes in electric double-layer capacitors. J Phys Chem Lett 4(8):1260–1267

    Article  CAS  Google Scholar 

  10. Neal JN, Wesolowski DJ, Henderson D, Wu J (2018) Electric double layer capacitance for ionic liquids in nanoporous electrodes: Effects of pore size and ion composition. J Mol Liq 270:145–150

    Article  CAS  Google Scholar 

  11. Lian C, Jiang De, Liu H, Wu J (2016) A generic model for electric double layers in porous electrodes. J Phys Chem C 120(16):8704–8710

    Article  CAS  Google Scholar 

  12. Feng G, Jiang De, Cummings PT (2012) Curvature effect on the capacitance of electric double layers at ionic liquid/onion-like carbon interfaces. J Chem Theory Comput 8(3):1058–1063

    Article  CAS  Google Scholar 

  13. Keshavarzi E, Abareghi M, Helmi A (2019) Curvature dependence of the camel-bell curve transition on the capacitance curve of spherical electric double-layer in porous electrodes: density functional theory. Electrochim Acta 313:303–310

    Article  CAS  Google Scholar 

  14. Ma K, Woodward CE, Forsman J (2014) Classical density functional study on interfacial structure and differential capacitance of ionic liquids near charged surfaces. J Phys Chem C 118(29):15825–15834

    Article  CAS  Google Scholar 

  15. Kornyshev AA (2007) Double-layer in ionic liquids: paradigm change? J Phys Chem B 111(20):5545–5557

    Article  CAS  Google Scholar 

  16. Goodwin ZA, Feng G, Kornyshev AA (2017) Mean-field theory of electrical double layer in ionic liquids with account of short-range correlations. Electrochim Acta 225:190–197

    Article  CAS  Google Scholar 

  17. Keshavarzi E, Abareghi M (2020) The effect of electro-neutrality violation inside a charged spherical cavity on the capacitance curve shape in DFT approach and interpretation of mean electrostatic potential. J Mol Liq. https://doi.org/10.1016/j.molliq.2020.114271

    Article  Google Scholar 

  18. Fedorov MV, Georgi N, Kornyshev AA (2010) Double layer in ionic liquids: the nature of the camel shape of capacitance. Electrochem Commun 12(2):296–299

    Article  CAS  Google Scholar 

  19. Islam MM, Alam MT, Ohsaka T (2008) Electrical double-layer structure in ionic liquids: a corroboration of the theoretical model by experimental results. J Phys Chem C 112(42):16568–16574

    Article  CAS  Google Scholar 

  20. Lamperski S, Outhwaite CW, Bhuiyan LB (2009) The electric double-layer differential capacitance at and near zero surface charge for a restricted primitive model electrolyte. J Phys Chem B 113(26):8925–8929

    Article  CAS  Google Scholar 

  21. Pizio O, Sokołowski S, Sokołowska Z (2012) Electric double layer capacitance of restricted primitive model for an ionic fluid in slit-like nanopores: a density functional approach. J Chem Phys 137(23):234705

    Article  CAS  Google Scholar 

  22. Shen G, Sun Y, Wang Y, Lu X, Ji X (2020) Interfacial structure and differential capacitance of ionic liquid/graphite interface: a perturbed-chain SAFT density functional theory study. J Mol Liq 310:113199. https://doi.org/10.1016/j.molliq.2020.113199

    Article  CAS  Google Scholar 

  23. Henderson D, Silvestre-Alcantara W, Kaja M, Lamperski S, Wu J, Bhuiyan LB (2017) Structure and capacitance of an electric double layer of an asymmetric valency dimer electrolyte: a comparison of the density functional theory with Monte Carlo simulations. J Mol Liq 228:236–242

    Article  CAS  Google Scholar 

  24. Henderson D (2012) Oscillations in the capacitance of a nanopore containing an electrolyte due to pore width and nonzero size ions. J Colloid Interface Sci 374(1):345–347

    Article  CAS  Google Scholar 

  25. Bossa GV, Caetano DL, de Carvalho SJ, Bohinc K, May S (2018) Modeling the camel-to-bell shape transition of the differential capacitance using mean-field theory and Monte Carlo simulations. The Eur Phys J E 41(9):1–9

    Article  CAS  Google Scholar 

  26. Trulsson M, Algotsson J, Forsman J, Woodward CE (2010) Differential capacitance of room temperature ionic liquids: the role of dispersion forces. J Phys Chem Lett 1(8):1191–1195

    Article  CAS  Google Scholar 

  27. Pizio O, Sokołowski S (2013) Restricted primitive model for electrolyte solutions in slit-like pores with grafted chains: microscopic structure, thermodynamics of adsorption, and electric properties from a density functional approach. J Chem Phys 138(20):204715

    Article  Google Scholar 

  28. Faramarzi E, Maghari A (2017) The effect of dispersion interactions on the structure and performance of electrical double layer of ionic liquids. J Mol Liq 246:325–331

    Article  CAS  Google Scholar 

  29. Zhou S (2018) Capacitance of electrical double layer formed inside a single infinitely long cylindrical pore. J Stat Mech 2018(10):103203

    Article  Google Scholar 

  30. Yu Y-X, Wu J, Gao GH (2004) Density-functional theory of spherical electric double layers and ζ potentials of colloidal particles in restricted-primitive-model electrolyte solutions. J Chem Phys 120(15):7223–7233

    Article  CAS  Google Scholar 

  31. Mansoori G, Carnahan NF, Starling K, Leland T Jr (1971) Equilibrium thermodynamic properties of the mixture of hard spheres. J Chem Phys 54(4):1523–1525

    Article  CAS  Google Scholar 

  32. Rosenfeld Y (1989) Free-energy model for the inhomogeneous hard-sphere fluid mixture and density-functional theory of freezing. Phys Rev Lett 63(9):980

    Article  CAS  Google Scholar 

  33. Degrève L, Lozada-Cassou M, Sánchez E, González-Tovar E (1993) Monte Carlo simulation for a symmetrical electrolyte next to a charged spherical colloid particle. J Chem Phys 98(11):8905–8909

    Article  Google Scholar 

Download references

Acknowledgements

The authors would like to acknowledge Isfahan University of Technology. Dr. Ezzatollah Roustazadeh from The English Language Center of Isfahan University of Technology also deserves our gratitude for editing the final English manuscript.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Ezat Keshavarzi.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Keshavarzi, E., Rabiei-Jildani, S. & Abareghi, M. A new regularity used to predict the camel-bell shape transition in the capacitance curve of electric double layer capacitors. J Appl Electrochem 51, 1229–1240 (2021). https://doi.org/10.1007/s10800-021-01571-z

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10800-021-01571-z

Keywords

Navigation