Skip to main content
Log in

Highly porous activated glassy carbon film sandwich structure for electrochemical energy storage in ultracapacitor applications: Study of the porous film structure and gradient

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

Abstract

Glassy carbon plates were thermochemically gas phase oxidized to obtain monolithic sandwichlike electrode assemblies with high surface area porous films for electrochemical energy storage applications. Film thicknesses were varied by variation of oxidation parameters time, temperature, and oxygen concentration and measured with electron microscopy. The mass density of the porous carbon film material was estimated by fitting a geometrical model to experimental gravimetric data. Optical Raman spectroscopy line scans suggest that the porosity has a gradient between the surface and the film/bulk interface, which is supported by pore-size distribution data obtained from small-angle x-ray scattering (SAXS) on slightly oxidized and fully oxidized samples. Detailed inspection of the power law behavior of SAXS data suggests that the internal surface area of well-oxidized glassy carbon (GC) is compact and extends over the entire probed volume and thus has optimal pore connectivity. This effect goes along with pore enlargement and a relative decrease of internal surface area per volume. Slightly oxidized carbon has no pore space with a compact, high connectivity internal surface area. The corresponding SAXS power law and the x-ray density suggest that this high volumetric surface area must be interpreted as a result of surface roughness, rather than true geometric or volumetric surface area. In consequence, is this surface area of limited use for electrochemical energy storage?

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.

Similar content being viewed by others

References

  1. J.C. Lewis, B. Redfern, F.C. Cowlard: Vitreous carbon as a crucible material for semiconductors. Solid-State Electron.6, (3) 251 (1963)

    Article  CAS  Google Scholar 

  2. G.M. Jenkins, K. Kawamura Polymeric Carbons—Carbon Fiber, Glass and Char1st ed (Cambridge University Press, Cambridge UK 1976)

    Google Scholar 

  3. A. Braun, M. Bärtsch, B. Schnyder, R. Kötz: A model for the film growth in samples with two moving boundaries—An application and extension of the unreacted-core model. Chem. Eng. Sci.55, (22) 5245 (2000)

    Article  Google Scholar 

  4. A. Braun, A. Wokaun, H-G. Hermanns: Analytical solution to a growth problem with two moving boundaries. Appl. Math. Model27, (1) 47 (2003)

    Article  Google Scholar 

  5. J.C. Lewis, I.J. Floyd, F.C. Cowlard: A comparative study of gaseous oxidation of vitreous carbon and various graphites at 1500-3000 degrees K. Carbon6, (2) 223 (1968)

    Article  Google Scholar 

  6. J. Miklos, K. Mund, W. Naschwitz: Patent DE 30 11 701 A1. Siemens AG and German Patent Office (1980)

    Google Scholar 

  7. A. Braun, M. Bärtsch, B. Schnyder, R. Kötz, O. Haas, H-G. Haubold, G. Goerigk: X-ray scattering and adsorption studies of thermally oxidized glassy carbon. J. Non-Cryst. Solids260, (1-2) 1 (1999)

    Article  CAS  Google Scholar 

  8. A. Braun, M. Bärtsch, F. Geiger, O. Haas, R. Kötz, B. Schnyder, M. Carlen, T. Christen, C. Ohler, P. Unternährer, H. Desilvestro, E. Krause: A study on oxidized glassy carbon sheets for bipolar supercapacitor electrodes New Materials for Batteries and Fueledited by D.H. Doughty, L.F. Nazar, M. Arakawa, H-P. Brack, and K. Naoi (Mater. Res. Soc. Symp. Proc 575Warrendale, PA 1999)369

    Google Scholar 

  9. A. Braun, M. Bärtsch, O. Merlo, B. Schaffner, B. Schnyder, R. Kötz, O. Haas, A. Wokaun: Evolution of electrochemical double layer capacitance in glassy carbon during thermal oxidation—Crossover from exponential to logistic growth. Carbon41, (4) 759 (2003)

    Article  CAS  Google Scholar 

  10. A. Braun, M. Bärtsch, B. Schnyder, R. Kötz, O. Haas, A. Wokaun: Evolution of BET internal surface area in glassy carbon powder during thermal oxidation. Carbon40, (3) 375 (2002)

    Article  CAS  Google Scholar 

  11. M. Bärtsch, A. Braun, B. Schnyder, R. Kötz, O. Haas: Bipolar glassy carbon electrochemical double-layer capacitor: 100,000 cycles demonstrated. J. New Mater. Electrochem. Syst.2273 (1999)

    Google Scholar 

  12. B.E. Conway, W.G. Pell: Double-layer and pseudocapacitance types of electrochemical capacitors and their applications to the development of hybrid devices. J. Solid State Electrochem.7, (9) 637 (2003)

    Article  CAS  Google Scholar 

  13. A. Braun, J. Kohlbrecher, M. Bärtsch, B. Schnyder, R. Kötz, O. Haas, A. Wokaun: Small angle neutron scattering and cyclic voltammetry study on electrochemically oxidized and reduced pyrolytic carbon. Electrochim. Acta49, (7) 1105 (2004)

    Article  CAS  Google Scholar 

  14. W.S. Rothwell: Small-angle x-ray scattering from glassy carbon. J. Appl. Phys.39, (3) 1840 (1968)

    Article  CAS  Google Scholar 

  15. J. Ilavsky, P.R. Jemian, A.J. Allen, F. Zhang, L.E. Levine, G.G. Long: Ultra-small-angle x-ray scattering at the advanced photon source. J. Appl. Crystallogr.42, (3) 469 (2009)

    Article  CAS  Google Scholar 

  16. J. Ilavsky, P.R. Jemian Irena: Tool suite for modeling and analysis of small-angle scattering. J. Appl. Crystallogr.42, (2) 347 (2009)

    Article  CAS  Google Scholar 

  17. O. Glatter, O. Kratky Small Angle X-Ray Scattering, (Academic Press, New York)

  18. M.E. Spahr, T. Palladino, H. Wilhelm, A. Würsig, D. Goers, H. Buqa, M. Holzapfel, P. Novak J Electrochem Soc.151, (9) A1383 (2004)

    Article  CAS  Google Scholar 

  19. H.J. Vogel: Morphological determination of pore connectivity as a function of pore size using serial sections. Eur. J. Soil Sci.48, (3) 365 (1997)

    Article  Google Scholar 

  20. P. Wong, A.J. Bray: Scattering by rough surfaces. Phys. Rev. B377751 (1988)

    Article  CAS  Google Scholar 

  21. A.J. Allen, J. Ilavsky, A. Braun: Multi-scale microstructure characterization of solid oxide fuel cell assemblies with ultra small-angle x-ray scattering. Adv. Eng. Mater.11, (6) 495 (2009)

    Article  CAS  Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Artur Braun.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Braun, A., Seifert, S. & Ilavsky, J. Highly porous activated glassy carbon film sandwich structure for electrochemical energy storage in ultracapacitor applications: Study of the porous film structure and gradient. Journal of Materials Research 25, 1532–1540 (2010). https://doi.org/10.1557/JMR.2010.0197

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1557/JMR.2010.0197

Navigation