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Ionomer distribution control in porous carbon-supported catalyst layers for high-power and low Pt-loaded proton exchange membrane fuel cells

Abstract

The reduction of Pt content in the cathode for proton exchange membrane fuel cells is highly desirable to lower their costs. However, lowering the Pt loading of the cathodic electrode leads to high voltage losses. These voltage losses are known to originate from the mass transport resistance of O2 through the platinum–ionomer interface, the location of the Pt particle with respect to the carbon support and the supports’ structures. In this study, we present a new Pt catalyst/support design that substantially reduces local oxygen-related mass transport resistance. The use of chemically modified carbon supports with tailored porosity enabled controlled deposition of Pt nanoparticles on the outer and inner surface of the support particles. This resulted in an unprecedented uniform coverage of the ionomer over the high surface-area carbon supports, especially under dry operating conditions. Consequently, the present catalyst design exhibits previously unachieved fuel cell power densities in addition to high stability under voltage cycling. Thanks to the Coulombic interaction between the ionomer and N groups on the carbon support, homogeneous ionomer distribution and reproducibility during ink manufacturing process is ensured.

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Fig. 1: Overview of experimental approach and surface characterization.
Fig. 2: Morphological and structural characterization of catalysts synthesized in this study.
Fig. 3: Correlation of NH3 heat treatment on thermal stability and ORR activity.
Fig. 4: Effect of N modification on ionomer distribution and performance in fuel cell.
Fig. 5: Evaluation of the stability of the N-modified catalysts under potential cycling protocol.

Data availability

The data supporting the findings of this study are available within this article and its Supplementary Information files, or from the corresponding author upon reasonable request. The Supplementary Information contains descriptions of methods, discussion on physicochemical characterization and the electrochemical characterization of as-prepared/conducted CO stripping, polarization curves, limiting current measurements and accelerated stress testing. It also includes Supplementary Figs. 112 and Supplementary Tables 18.

References

  1. 1.

    US DRIVE Partnership. Fuel Cell Technical Team Roadmap, June 2013 https://energy.gov/sites/prod/files/2014/02/f8/fctt_roadmap_june2013.pdf (2013).

  2. 2.

    Ohma, A. et al. Analysis of proton exchange membrane fuel cell catalyst layers for reduction of platinum loading at Nissan. Electrochimica Acta 56, 10832–10841 (2011).

    CAS  Article  Google Scholar 

  3. 3.

    Ohma, A., Fushinobu, K. & Okazaki, K. Influence of Nafion film on oxygen reduction reaction and hydrogen peroxide formation on Pt electrode for proton exchange membrane fuel cell. Electrochimica Acta 55, 8829–8838 (2010).

    CAS  Article  Google Scholar 

  4. 4.

    Jinnouchi, R., Kudo, K., Kitano, N. & Morimoto, Y. Molecular ynamics simulations on O2 permeation through Nafion ionomer on platinum surface. Electrochimica Acta 188, 767–776 (2016).

    CAS  Article  Google Scholar 

  5. 5.

    Shinozaki, K., Morimoto, Y., Pivovar, B. S. & Kocha, S. S. Suppression of oxygen reduction reaction activity on Pt-based electrocatalysts from ionomer incorporation. J. Power Source. 325, 745–751 (2016).

    CAS  Article  Google Scholar 

  6. 6.

    Yarlagadda, V. C. et al. Boosting fuel cell performance with accessible carbon mesopores. ACS Energy Lett. 3, 618–621 (2018).

    CAS  Article  Google Scholar 

  7. 7.

    Lopez-Haro, M. et al. Three-dimensional analysis of Nafion layers in fuel cell electrodes. Nat. Commun. 5, 5229 (2014).

    CAS  Article  Google Scholar 

  8. 8.

    Orfanidi, A. et al. The key to high performance low Pt loaded electrodes. J. Electrochem. Soc. 164, F418–F426 (2017).

    CAS  Article  Google Scholar 

  9. 9.

    Sun, L.-X. & Okada, T. Studies on interactions between Nafion and organic vapours by quartz crystal microbalance. J. Memb. Sci. 183, 213–221 (2001).

    CAS  Article  Google Scholar 

  10. 10.

    Miyazaki, K. et al. Aminated perfluorosulfonic acid ionomers to improve the triple phase boundary region in anion exchange membrane fuel cells. J. Electrochem. Soc. 157, A1153–A1157 (2010).

    CAS  Article  Google Scholar 

  11. 11.

    Owejan, J. P., Owejan, J. E. & Gu, W. Impact of platinum loading and catalyst layer structure on PEMFC performance. J. Electrochem. Soc. 160, F824–F833 (2013).

    CAS  Article  Google Scholar 

  12. 12.

    Jansen, R. J. J. & van Bekkum, H. XPS of nitrogen-containing functional groups on activated carbon. Carbon 33, 1021–1027 (1995).

    CAS  Article  Google Scholar 

  13. 13.

    Ortega, K. F., Arrigo, R., Frank, B., Schlögl, R. & Trunschke, A. Acid–base properties of N-doped carbon nanotubes: a combined temperature-programmed desorption, X-ray photoelectron spectroscopy, and 2-propanol reaction investigation. Chem. Mat. 28, 6826–6839 (2016).

    Article  Google Scholar 

  14. 14.

    Mikhail, R. S., Brunauer, S. & Bodor, N. E. E. Investigations of a complete pore structure analysis. J. Colloid Inter. Sci. 26, 45–53 (1968).

    CAS  Article  Google Scholar 

  15. 15.

    Lowell, S., Shields, J. E., Thomas, M. A. & Thommes, M. Characterization of Porous Solids and Powder: Surface Area, Pore Size and Density (Kluwer Academic, 2004).

  16. 16.

    Jaouen, F. & Dodelet, J.-P. Non-noble electrocatalysts for O2 reduction: how does heat treatment affect their activity and structure? Part I. Model for carbon black gasification by NH3: parametric calibration and electrochemical validation. J. Phys. Chem. C. 111, 5963–5970 (2007).

    CAS  Article  Google Scholar 

  17. 17.

    Sherwood, T. K., Gilliland, E. R. & Ing, S. W. Hydrogen cyanide synthesis from elements and from ammonia and carbon. Indust. Eng. Chem. 52, 601–604 (1960).

    CAS  Article  Google Scholar 

  18. 18.

    Arrigo, R., Hävecker, M., Schlögl, R. & Su, D. S. Dynamic surface rearrangement and thermal stability of nitrogen functional groups on carbon nanotubes. Chem. Comm. 40, 4891–4893 (2008).

    Article  Google Scholar 

  19. 19.

    Harzer, G. S., Orfanidi, A., El-Sayed, H., Madkikar, P. & Gasteiger, H. A. Tailoring catalyst morphology towards high performance for low Pt loaded PEMFC cathodes. J. Electrochem. Soc. 165, F770–F779 (2018).

    CAS  Article  Google Scholar 

  20. 20.

    Park, Y.-C., Tokiwa, H., Kakinuma, K., Watanabe, M. & Uchida, M. Effects of carbon supports on Pt distribution, ionomer coverage and cathode performance for polymer electrolyte fuel cells. J. Power Source. 315, 179–191 (2016).

    CAS  Article  Google Scholar 

  21. 21.

    Neyerlin, K. C., Gu, W., Jorne, J. & Gasteiger, H. A. Determination of catalyst unique parameters for the oxygen reduction reaction in a PEMFC. J. Electrochem. Soc. 153, A1955–A1963 (2006).

    CAS  Article  Google Scholar 

  22. 22.

    Kabir, S., Artyushkova, K., Serov, A. & Atanassov, P. Role of nitrogen moieties in N-doped 3D-graphene nanosheets for oxygen electroreduction in acidic and alkaline media. ACS App. Mat. Int. 10, 11623–11632 (2018).

    CAS  Article  Google Scholar 

  23. 23.

    Lai, L. et al. Exploration of the active center structure of nitrogen-doped graphene-based catalysts for oxygen reduction reaction. Energy Environ. Sci. 5, 7936 (2012).

    CAS  Article  Google Scholar 

  24. 24.

    Yang, S. et al. Efficient synthesis of heteroatom (N or S)-doped graphene based on ultrathin graphene oxide-porous silica sheets for oxygen reduction reactions. Adv. Funct. Mat. 22, 3634–3640 (2012).

    CAS  Article  Google Scholar 

  25. 25.

    Artyushkova, K. et al. Role of surface chemistry on catalyst/ionomer interactions for transition metal–nitrogen–carbon electrocatalysts. ACS Appl. Energy Mat. 1, 68–77 (2017).

    Article  Google Scholar 

  26. 26.

    Ohma, A. et al. Membrane and catalyst performance targets for automotive fuel cells by FCCJ membrane. ECS Trans. 41, 775–784 (2011).

    CAS  Article  Google Scholar 

  27. 27.

    Kongkanand, A. & Mathias, M. F. The priority and challenge of high-power performance of low-platinum proton-exchange membrane fuel cells. J. Phys. Chem. Lett. 7, 1127–1137 (2016).

    CAS  Article  Google Scholar 

  28. 28.

    Orfanidi, A., Rheinlander, P. J., Schulte, N. & Gasteiger, H. A. Ink solvent dependence of the ionomer distribution in the catalyst layer of a PEMFC. J. Electrochem. Soc. 165, F1254–F1263 (2018).

    CAS  Article  Google Scholar 

  29. 29.

    Harzer, G. S., Schwammlein, J. N., Damjanovic, A. M., Ghosh, S. & Gasteiger, H. A. Cathode loading impact on voltage cycling induced PEMFC degradation: a voltage loss analysis. J. Electrochem. Soc. 165, F3118–F3131 (2018).

    CAS  Article  Google Scholar 

  30. 30.

    Schmies, H. et al. Impact of carbon support functionalization on the electrochemical stability of Pt fuel cell catalysts. Chem. Mater. 30, 7287–7295 (2018).

    CAS  Article  Google Scholar 

  31. 31.

    Zhou, Y. et al. Enhancement of Pt and Pt-alloy fuel cell catalyst activity and durability via nitrogen-modified carbon supports. Energy Environ. Sci. 3, 1437–1446 (2010).

    CAS  Article  Google Scholar 

  32. 32.

    Shi, W. et al. Enhanced stability of immobilized platinum nanoparticles through nitrogen heteroatoms on doped carbon supports. Chem. Mater. 29, 8670–8678 (2017).

    CAS  Article  Google Scholar 

  33. 33.

    Baker, D. R. C. C. A., Neyerlin, K. C. & Murph, M. W. Measurement of oxygen transport resistance in PEM fuel cells by limiting current methods. J. Electrochem. Soc. 156, B991–B1003 (2009).

    CAS  Article  Google Scholar 

  34. 34.

    Caulk, D. A. & Baker, D. R. Heat and water transport in hydrophobic diffusion media of PEM fuel cells. J. Electrochem. Soc. 157, B1237–B1244 (2010).

    CAS  Article  Google Scholar 

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Acknowledgements

This work was supported by the BMW Group. We also thank the members of FC Test Field, FC Technology Development and Technology Material Analysis of BMW Group for their support during fuel cell testing, MEA manufacturing and decal preparation.

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Contributions

A.O. conceived the project. S.O. synthesized all the samples. S.O. and A.O. carried out the MEA manufacturing, fuel cell experiments and data analysis. H.S. and B.A. contributed to material synthesis including ammonolysis. H.N.N. conducted and analysed XPS measurements. J.H. conducted and analysed nitrogen physisorption measurements. U.G. carried out SEM/STEM measurements. M.G. carried out TGA measurements. P.S. provided guidance and constructive ideas throughout the project to ensure the successful outcome of this project. All authors contributed to the discussion part, drew conclusions and participated in finalizing the text and figures.

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Correspondence to Alin Orfanidi or Peter Strasser.

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Ott, S., Orfanidi, A., Schmies, H. et al. Ionomer distribution control in porous carbon-supported catalyst layers for high-power and low Pt-loaded proton exchange membrane fuel cells. Nat. Mater. 19, 77–85 (2020). https://doi.org/10.1038/s41563-019-0487-0

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