Pore network tortuosity controls fast charging in supercapacitors
Source abstract
Abstract
Abstract Ionic transport within porous carbon electrodes is crucial for optimizing charge and discharge rates in supercapacitors, yet the material properties governing ion dynamics remain poorly understood. Unlike the traditional viewpoint, here we find that mesoporosity does not necessarily correlate with a high supercapacitor rate capability. We employed pulsed-field-gradient nuclear magnetic resonance to directly measure the anionic effective diffusivities in the carbon pores. This technique probes ionic transport in supercapacitors. Our findings reveal a major discrepancy between short-range and long-range diffusivities, which captures the tortuosity of the pore network. Short-range diffusivities lack correlation with supercapacitor rate capability, whereas long-range diffusivities correlate strongly. Low-tortuosity nanoporous carbon exhibited superior rate capability, which highlights the importance of well-interconnected pore networks for efficient ion transport. Our study reveals that the pore network tortuosity is a key factor governing charging rates in amorphous nanoporous carbon and that it can be used to guide the design of electrodes with optimized transport channels to enhance supercapacitor performance.
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Research context
OpenAlex topics: Supercapacitor Materials and Fabrication · Nanopore and Nanochannel Transport Studies · Fuel Cells and Related Materials
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References (58)
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1. Zhang, L. L. & Zhao, X. S. Carbon-based materials as supercapacitor electrodes. Chem. Soc. Rev. 38, 2520 (2009).10.1039/b813846j ↗
2. Simon, P. & Gogotsi, Y. Perspectives for electrochemical capacitors and related devices. Nat. Mater. 19, 1151–1163 (2020).10.1038/s41563-020-0747-z ↗
3. Meunier, V. et al. Carbon science perspective in 2024: current research and future challenges. Carbon 229, 119488 (2024).10.1016/j.carbon.2024.119488 ↗
4. Gogotsi, Y. et al. Nanoporous carbide-derived carbon with tunable pore size. Nat. Mater. 2, 591–594 (2003).10.1038/nmat957 ↗
5. Zhao, J. & Burke, A. F. Electrochemical capacitors: materials, technologies and performance. Energy Storage Mater. 36, 31–55 (2021).10.1016/j.ensm.2020.12.013 ↗
6. Doyle, M. & Newman, J. J. Analysis of capacity–rate data for lithium batteries using simplified models of the discharge process. J. Appl. Electrochem. 27, 846–856 (1997).10.1023/A:1018481030499 ↗
7. Johns, P. A., Roberts, M. R., Wakizaka, Y., Sanders, J. H. & Owen, J. R. How the electrolyte limits fast discharge in nanostructured batteries and supercapacitors. Electrochem. Commun. 11, 2089–2092 (2009).10.1016/j.elecom.2009.09.001 ↗
8. Teng, C. et al. Isostatic pressure-assisted nanocasting preparation of zeolite templated carbon for high-performance and ultrahigh rate capability supercapacitors. J. Mater. Chem. A 6, 18938–18947 (2018).10.1039/C8TA05726E ↗
9. Liu, L. et al. Evaluating the role of nanostructured current collectors in energy storage capability of supercapacitor electrodes with thick electroactive materials layers. Adv. Funct. Mater. 28, 1705107 (2018).10.1002/adfm.201705107 ↗
10. E, L. et al. High-performance supercapacitor device with ultrathick electrodes fabricated from all-cellulose-based carbon aerogel. Energy Fuels 35, 8295–8302 (2021).10.1021/acs.energyfuels.0c04092 ↗
11. Wang, F. et al. Inspired by wood: thick electrodes for supercapacitors. ACS Nano 17, 8866–8898 (2023).10.1021/acsnano.3c01241 ↗
12. Yamada, H., Nakamura, H., Nakahara, F., Moriguchi, I. & Kudo, T. Electrochemical study of high electrochemical double layer capacitance of ordered porous carbons with both meso/macropores and micropores. J. Phys. Chem. C 111, 227–233 (2007).10.1021/jp063902g ↗
13. Wang, K., Wang, Y., Wang, Y., Hosono, E. & Zhou, H. Mesoporous carbon nanofibers for supercapacitor application. J. Phys. Chem. C 113, 1093–1097 (2009).10.1021/jp807463u ↗
14. Liu, H., Wang, J., Wang, C. & Xia, Y. Ordered hierarchical mesoporous/microporous carbon derived from mesoporous titanium-carbide/carbon composites and its electrochemical performance in supercapacitor. Adv. Energy Mater. 1, 1101–1108 (2011).10.1002/aenm.201100255 ↗
15. Rauda, I. E., Augustyn, V., Dunn, B. & Tolbert, S. H. Enhancing pseudocapacitive charge storage in polymer templated mesoporous materials. Acc. Chem. Res. 46, 1113–1124 (2013).10.1021/ar300167h ↗
16. Karthik, M. et al. Effect of mesopore ordering in otherwise similar micro/mesoporous carbons on the high-rate performance of electric double-layer capacitors. J. Phys. Chem. C 118, 27715–27720 (2014).10.1021/jp508581x ↗
17. Fang, Y., Zhang, Q. & Cui, L. Recent progress of mesoporous materials for high performance supercapacitors. Microporous Mesoporous Mater. 314, 110870 (2021).10.1016/j.micromeso.2020.110870 ↗
18. Korenblit, Y. et al. High-rate electrochemical capacitors based on ordered mesoporous silicon carbide-derived carbon. ACS Nano 4, 1337–1344 (2010).10.1021/nn901825y ↗
19. Reale, E. R. & Smith, K. C. Capacitive performance and tortuosity of activated carbon electrodes with macroscopic pores. J. Electrochem. Soc. 165, A1685–A1693 (2018).10.1149/2.0601809jes ↗
20. Bhat, A. P., Reale, E. R., Del Cerro, M., Smith, K. C. & Cusick, R. D. Reducing impedance to ionic flux in capacitive deionization with Bi-tortuous activated carbon electrodes coated with asymmetrically charged polyelectrolytes. Water Res. X 3, 100027 (2019).
21. Borchardt, L., Leistenschneider, D., Haase, J. & Dvoyashkin, M. Revising the concept of pore hierarchy for ionic transport in carbon materials for supercapacitors. Adv. Energy Mater. 8, 1800892 (2018).10.1002/aenm.201800892 ↗
22. Dvoyashkin, M., Leistenschneider, D., Evans, J. D., Sander, M. & Borchardt, L. Revealing the impact of hierarchical pore organization in supercapacitor electrodes by coupling ionic dynamics at micro- and macroscales. Adv. Energy Mater. 11, 2100700 (2021).10.1002/aenm.202100700 ↗
23. Jänes, A. & Lust, E. Electrochemical characteristics of nanoporous carbide-derived carbon materials in various nonaqueous electrolyte solutions. J. Electrochem. Soc. 153, A113 (2006).10.1149/1.2135212 ↗
24. Terban, M. W. & Billinge, S. J. L. Structural analysis of molecular materials using the pair distribution function. Chem. Rev. 122, 1208–1272 (2022).10.1021/acs.chemrev.1c00237 ↗
25. Balach, J. et al. A direct and quantitative image of the internal nanostructure of nonordered porous monolithic carbon using FIB nanotomography. J. Microsc. 246, 274–278 (2012).10.1111/j.1365-2818.2012.03615.x ↗
26. Balach, J., Soldera, F., Acevedo, D. F., Mücklich, F. & Barbero, C. A. A Direct and Quantitative Three-Dimensional Reconstruction of the Internal Structure of Disordered Mesoporous Carbon with Tailored Pore Size. Microsc. Microanal. 19, 745–750 (2013).10.1017/S1431927613000238 ↗
27. Zacharias, N. A. et al. Direct measurements of effective ionic transport in porous Li-ion electrodes. J. Electrochem. Soc. 160, A306–A311 (2013).10.1149/2.062302jes ↗
28. Tjaden, B., Cooper, S. J., Brett, D. J., Kramer, D. & Shearing, P. R. On the origin and application of the Bruggeman correlation for analysing transport phenomena in electrochemical systems. Curr. Opin. Chem. Eng. 12, 44–51 (2016).10.1016/j.coche.2016.02.006 ↗
29. Stallmach, F. & Kärger, J. The potentials of pulsed field gradient NMR for investigation of porous media. Adsorption 5, 117–133 (1999).10.1023/A:1008949607093 ↗
30. Valiullin, R. (ed.) Diffusion NMR of Confined Systems:Fluid Transport in Porous Solids and Heterogeneous Materials (Royal Society of Chemistry, 2017); https://doi.org/10.1039/978178262377910.1039/9781782623779 ↗
31. Zecca, M., Vogt, S. J., Connolly, P. R. J., May, E. F. & Johns, M. L. NMR measurements of tortuosity in partially saturated porous media. Transp. Porous Media 125, 271–288 (2018).10.1007/s11242-018-1118-y ↗
32. Linck, L. G. et al. Limits imposed by liquid/surface interactions in the determination of tortuosity in mesopores. Microporous Mesoporous Mater. 305, 110351 (2020).10.1016/j.micromeso.2020.110351 ↗
33. Sen, P. N. Time-dependent diffusion coefficient as a probe of geometry. Concepts Magn. Reson. Part A 23A, 1–21 (2004).10.1002/cmr.a.20017 ↗
34. Yang, K. et al. Quantitative tortuosity measurements of carbonate rocks using pulsed field gradient NMR. Transp. Porous Media 130, 847–865 (2019).10.1007/s11242-019-01341-8 ↗
35. Chang, K. et al. Influence of rubbery versus glassy backbone dynamics on multiscale transport in polymer membranes. Macromolecules 51, 9222–9233 (2018).10.1021/acs.macromol.8b01830 ↗
36. Thieu, L. M., Zhu, L., Korovich, A. G., Hickner, M. A. & Madsen, L. A. Multiscale tortuous diffusion in anion and cation exchange membranes. Macromolecules 52, 24–35 (2019).10.1021/acs.macromol.8b02206 ↗
37. Forse, A. C. et al. Direct observation of ion dynamics in supercapacitor electrodes using in situ diffusion NMR spectroscopy. Nat. Energy 2, 16216 (2017).10.1038/nenergy.2016.216 ↗
38. Forse, A. C. et al. NMR study of ion dynamics and charge storage in ionic liquid supercapacitors. J. Am. Chem. Soc. 137, 7231–7242 (2015).10.1021/jacs.5b03958 ↗
39. Liu, X. et al. Structural disorder determines capacitance in nanoporous carbons. Science 384, 321–325 (2024).10.1126/science.adn6242 ↗
40. Zhu, T. et al. Ion-pore size match effects and high-performance cucurbit[8]uril-carbon-based supercapacitors. Electrochim. Acta 405, 139827 (2022).10.1016/j.electacta.2021.139827 ↗
41. Nguyen, H. V. T. et al. Size effect of electrolyte ions on the electric double-layer structure and supercapacitive behavior. ACS Appl. Energy Mater. 6, 3155–3166 (2023).10.1021/acsaem.3c00170 ↗
42. Fulik, N. et al. Electrolyte mobility in supercapacitor electrodes – solid state NMR studies on hierarchical and narrow pore sized carbons. Energy Storage Mater. 12, 183–190 (2018).10.1016/j.ensm.2017.12.008 ↗
43. Borchardt, L., Oschatz, M., Paasch, S., Kaskel, S. & Brunner, E. Interaction of electrolyte molecules with carbon materials of well-defined porosity: characterization by solid-state NMR spectroscopy. Phys. Chem. Chem. Phys. 15, 15177 (2013).10.1039/c3cp52283k ↗
44. Xing, Y.-Z., Luo, Z.-X., Kleinhammes, A. & Wu, Y. Probing carbon micropore size distribution by nucleus independent chemical shift. Carbon 77, 1132–1139 (2014).10.1016/j.carbon.2014.06.031 ↗
45. Forse, A. C., Griffin, J. M., Presser, V., Gogotsi, Y. & Grey, C. P. Ring current effects: factors affecting the NMR chemical shift of molecules adsorbed on porous carbons. J. Phys. Chem. C 118, 7508–7514 (2014).10.1021/jp502387x ↗
46. Wu, D. H., Chen, A. D. & Johnson, C. S. An improved diffusion-ordered spectroscopy experiment incorporating bipolar-gradient pulses. J. Magn. Reson. Ser. A 115, 260–264 (1995).10.1006/jmra.1995.1176 ↗
47. Cervini, L., Barrow, N. & Griffin, J. Observing solvent dynamics in porous carbons by nuclear magnetic resonance: elucidating molecular-level dynamics of in-pore and ex-pore species. Johns. Matthey Technol. Rev. 64, 152–164 (2020).10.1595/205651320X15747624015789 ↗
48. Mitra, P. P., Sen, P. N. & Schwartz, L. M. Short-time behavior of the diffusion coefficient as a geometrical probe of porous media. Phys. Rev. B 47, 8565–8574 (1993).10.1103/PhysRevB.47.8565 ↗
49. Li, S., Li, Z., Xu, D., Feng, G. & Hu, R. Porosity and tortuosity: keys for accurate modeling of porous electrodes in supercapacitors. Mater. Today Phys. 36, 101174 (2023).10.1016/j.mtphys.2023.101174 ↗
50. Claridge, T. D. W. in Tetrahedron Organic Chemistry Series, Vol. 27 (ed. Claridge, T. D. W.) 303–334 (Elsevier, 2009).
51. Chen, C. et al. All-wood, low tortuosity, aqueous, biodegradable supercapacitors with ultra-high capacitance. Energy Environ. Sci. 10, 538–545 (2017).10.1039/C6EE03716J ↗
52. Bard, A. J., Faulkner, L. R. & White, H. S. Electrochemical Methods: Fundamentals and Applications (Wiley, 2022).
53. Lian, C., Janssen, M., Liu, H. & Van Roij, R. Blessing and curse: how a supercapacitor’s large capacitance causes its slow charging. Phys. Rev. Lett. 124, 076001 (2020).10.1103/PhysRevLett.124.076001 ↗
54. Tao, H., Xu, Z., Lian, C., Van Roij, R. & Liu, H. Charging dynamics in a laminate-electrode model for graphene-based supercapacitors. AIChE J. 69, e18189 (2023).10.1002/aic.18189 ↗
55. Liu, X. et al. Raman spectroscopy measurements support disorder-driven capacitance in nanoporous carbons. J. Am. Chem. Soc. 146, 30748–30752 (2024).10.1021/jacs.4c10214 ↗
56. Spees, W. M., Song, S., Garbow, J. R., Neil, J. J. & Ackerman, J. J. H. Use of ethylene glycol to evaluate gradient performance in gradient-intensive diffusion MR sequences. Magn. Reson. Med. 68, 319–324 (2012).10.1002/mrm.23201 ↗
57. Neimark, A. V., Lin, Y., Ravikovitch, P. I. & Thommes, M. Quenched solid density functional theory and pore size analysis of micro-mesoporous carbons. Carbon 47, 1617–1628 (2009).10.1016/j.carbon.2009.01.050 ↗
58. Kress, T., Liu, X. & Forse, A. C. Research data supporting ‘Pore network tortuosity controls fast charging in supercapacitors’. Apollo, Univ. of Cambridge Repository https://doi.org/10.17863/CAM.115051 (2025).10.17863/CAM.115051 ↗