Topics in Catalysis

, Volume 44, Issue 3, pp 461–468 | Cite as

Electrocatalysis and electrochemical promotion of CO oxidation in PEM fuel cells: the role of oxygen crossover

Article

The electrochemical promotion of catalysis (or NEMCA effect) was studied for the CO oxidation and water gas shift reaction on a Pt anode in a polymer electrolyte membrane (PEM) fuel cell. It was found that this phenomenon plays a significant role in a normal fuel cell operation (fuel mixture – air) but not in a hydrogen pumping operation (fuel mixture – H2). This implies that the role of oxygen crossover in the electropromotion (EP) of CO oxidation is vital. During fuel cell operation, the increase in the rate of CO consumption is 2.5 times larger than the electrochemical rate, I/2F of CO oxidation, while for oxygen bleeding conditions (fuel mixture + O2−air) the increase is five times larger than I/2F. This shows that the catalytic properties of the Pt anode are significantly modified by varying the catalyst potential. In order to confirm the role of oxygen crossover, Nafion membranes (117, 1135) with different thickness, were studied. The results show that upon decreasing the membrane thickness the crossover is increased and thus the electrochemical promotion effect becomes more pronounced.

Keywords

electrochemical promotion (NEMCA) PEM fuel cell CO-poisoning oxygen crossover PROX 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    Vayenas, C.G., Bebelis, S., Ladas, S. 1990Nature343625CrossRefGoogle Scholar
  2. 2.
    Vayenas, C.G., Bebelis, S., Pliangos, C., Brosda, S., Tsiplakides, D. 2001Electrochemical Activation of Catalysis: Promotion, Electrochemical Promotion and Metal-Support InteractionsKluwer Academic/Plenum PublishersNew YorkGoogle Scholar
  3. 3.
    Lambert, R.M., Williams, F., Palermo, A., Tihkov, M.S. 2000Topics Catal.1391CrossRefGoogle Scholar
  4. 4.
    Nicole, J., Tsiplakides, D., Wodiunig, S., Comninellis, C. 1997J. Electrochem. Soc.1441312CrossRefGoogle Scholar
  5. 5.
    Neophytides, S., Tsiplakides, D., Stonehart, P., Jaksic, M., Vayenas, C.G. 1994Nature370292CrossRefGoogle Scholar
  6. 6.
    Vayenas, C.G., Brosda, S., Pliangos, C. 2003J. Catal.216487CrossRefGoogle Scholar
  7. 7.
    Wagner, M., Schulze, N. 2003Electrochim. Acta483899CrossRefGoogle Scholar
  8. 8.
    Lee, S.J., Mukerjee, S., Ticianelli, E.A., McBreen, J. 1999Electrochim. Acta443283CrossRefGoogle Scholar
  9. 9.
    Gottesfeld, S., Pafford, J. 1988J. Electrochem. Soc.1352651CrossRefGoogle Scholar
  10. 10.
    Thomason, A.H., Lalk, T.R., Appleby, A.J. 2004J. Power Sources135204CrossRefGoogle Scholar
  11. 11.
    Carrette, L.P.L., Friedrich, K.A., Huber, M., Stimming, U. 2001Phys. Chem.3320CrossRefGoogle Scholar
  12. 12.
    Divisek, J., Oetjen, H.F., Peinecke, V., Schmidt, V.M., Stimming, U. 1998Electrochim. Acta433811CrossRefGoogle Scholar
  13. 13.
    He, C., Kunz, H.R., Fenton, J.M. 2001J. Electrochem. Soc.148A1116CrossRefGoogle Scholar
  14. 14.
    Katsaounis, A., Balomenou, S.P., Tsiplakides, D., Tsampas, M., Vayenas, C.G. 2005Electrochim. Acta505132CrossRefGoogle Scholar
  15. 15.
    Tsampas, M.N., Pikos, A., Brosda, S., Katsaounis, A., Vayenas, C.G. 2006Electrochim. Acta512743CrossRefGoogle Scholar
  16. 16.
    Liu, R., Smotkin, E.S. 2002J. Electroanal. Chem.53549CrossRefGoogle Scholar
  17. 17.
    Gurau, B., Smotkin, E.S. 2002J. Power Sources112339CrossRefGoogle Scholar
  18. 18.
    Tsiplakides, D., Neophytides, S., Enea, O., Jaksic, M.M., Vayenas, C.G. 1997J. Electrochem. Soc.1442072CrossRefGoogle Scholar
  19. 19.
    Ploense, L., Salazar, M., Gurau, B., Smotkin, E.S. 2000Solid State Ionics136–137713CrossRefGoogle Scholar
  20. 20.
    Ploense, L., Salazar, M., Gurau, B., Smotkin, E.S. 1997JACS11911550CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.Department of Chemical EngineeringUniversity of PatrasPatrasGreece

Personalised recommendations