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Graphene-nanopocket-encaged PtCo nanocatalysts for highly durable fuel cell operation under demanding ultralow-Pt-loading conditions

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Abstract

The proton exchange membrane fuel cell (PEMFC) as an attractive clean power source can promise a carbon-neutral future, but the widespread adoption of PEMFCs requires a substantial reduction in the usage of the costly platinum group metal (PGM) catalysts. Ultrafine nanocatalysts are essential to provide sufficient catalytic sites at a reduced PGM loading, but are fundamentally less stable and prone to substantial size growth in long-term operations. Here we report the design of a graphene-nanopocket-encaged platinum cobalt (PtCo@Gnp) nanocatalyst with good electrochemical accessibility and exceptional durability under a demanding ultralow PGM loading (0.070 mgPGM cm–2) due to the non-contacting enclosure of graphene nanopockets. The PtCo@Gnp delivers a state-of-the-art mass activity of 1.21 A mgPGM–1, a rated power of 13.2 W mgPGM–1 and a mass activity retention of 73% after an accelerated durability test. With the greatly improved rated power and durability, we project a 6.8 gPGM loading for a 90 kW PEMFC vehicle, which approaches that used in a typical catalytic converter.

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Fig. 1: Schematic of the protective nanopocket design and characterization of the PtCo@Gnp.
Fig. 2: The MA of Pt/C, c-PtCo/C and PtCo@Gnp tested in the MEAs and compared with representative catalysts in the literature.
Fig. 3: Polarization plots of MEAs with an ultralow PGM loading (total loading of 0.070 mgPGM cm–2 including both the cathode and anode) tested under H2/air.
Fig. 4: Characterization of catalysts at EOL, analysis of size distribution and corresponding MEA test results.

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All data that support the findings of this study are available in the main text, figures and Supplementary Information files. Further data enquiries can be addressed to the corresponding authors upon reasonable request.

References

  1. Debe, M. K. Electrocatalyst approaches and challenges for automotive fuel cells. Nature 486, 43–51 (2012).

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  3. Tollefson, J. Worth its weight in platinum. Nature 450, 334–335 (2007).

    Article  CAS  Google Scholar 

  4. Bossi, T. & Gediga, J. The environmental profile of platinum group metals. Johnson Matthey Technol. Rev. 61, 111–121 (2017).

    Article  CAS  Google Scholar 

  5. James, B. D., Huya-Kouadio, J. M., Houchins, C. & DeSantis, D. A. Mass Production Cost Estimation of Direct H2 PEM Fuel Cell Systems for Transportation Applications: 2018 Update (US DOE, 2018).

  6. Pollet, B. G., Kocha, S. S. & Staffell, I. Current status of automotive fuel cells for sustainable transport. Curr. Opin. Electrochem. 16, 90–95 (2019).

    Article  CAS  Google Scholar 

  7. Gröger, O., Gasteiger, H. A. & Suchsland, J.-P. Electromobility: batteries or fuel cells? J. Electrochem. Soc. 162, A2605–A2622 (2015).

    Article  CAS  Google Scholar 

  8. Hao, H. et al. Securing platinum-group metals for transport low-carbon transition. One Earth 1, 117–125 (2019).

    Article  Google Scholar 

  9. 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).

    Article  CAS  Google Scholar 

  10. Li, M. et al. Ultrafine jagged platinum nanowires enable ultrahigh mass activity for the oxygen reduction reaction. Science 354, 1414–1419 (2016).

    Article  CAS  Google Scholar 

  11. Escudero-Escribano, M. et al. Tuning the activity of Pt alloy electrocatalysts by means of the lanthanide contraction. Science 352, 73–76 (2016).

    Article  CAS  Google Scholar 

  12. Chen, C. et al. Highly crystalline multimetallic nanoframes with three-dimensional electrocatalytic surfaces. Science 343, 1339–1343 (2014).

    Article  CAS  Google Scholar 

  13. Greeley, J. et al. Alloys of platinum and early transition metals as oxygen reduction electrocatalysts. Nat. Chem. 1, 552–556 (2009).

    Article  CAS  Google Scholar 

  14. Zhang, L. et al. Platinum-based nanocages with subnanometer-thick walls and well-defined, controllable facets. Science 349, 412–416 (2015).

    Article  CAS  Google Scholar 

  15. Cui, C., Gan, L., Heggen, M., Rudi, S. & Strasser, P. Compositional segregation in shaped Pt alloy nanoparticles and their structural behaviour during electrocatalysis. Nat. Mater. 12, 765–771 (2013).

    Article  CAS  Google Scholar 

  16. Seh, Z. W. et al. Combining theory and experiment in electrocatalysis: insights into materials design. Science 355, eaad4998 (2017).

    Article  Google Scholar 

  17. Li, W., Chen, Z., Xu, L. & Yan, Y. A solution-phase synthesis method to highly active Pt-Co/C electrocatalysts for proton exchange membrane fuel cell. J. Power Sources 195, 2534–2540 (2010).

    Article  CAS  Google Scholar 

  18. Zhang, Z. et al. One-pot synthesis of highly anisotropic five-fold-twinned PtCu nanoframes used as a bifunctional electrocatalyst for oxygen reduction and methanol oxidation. Adv. Mater. 28, 8712–8717 (2016).

    Article  CAS  Google Scholar 

  19. Wang, X. X. et al. Ordered Pt3Co intermetallic nanoparticles derived from metal–organic frameworks for oxygen reduction. Nano Lett. 18, 4163–4171 (2018).

    Article  CAS  Google Scholar 

  20. Huang, L., Zheng, C. Y., Shen, B. & Mirkin, C. A. High-index-facet metal–alloy nanoparticles as fuel cell electrocatalysts. Adv. Mater. 32, 2002849 (2020).

    Article  CAS  Google Scholar 

  21. Ott, S. 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 (2019).

    Article  CAS  Google Scholar 

  22. Qiao, Z. et al. 3D porous graphitic nanocarbon for enhancing the performance and durability of Pt catalysts: a balance between graphitization and hierarchical porosity. Energy Environ. Sci. 12, 2830–2841 (2019).

    Article  CAS  Google Scholar 

  23. Wang, L. et al. Tunable intrinsic strain in two-dimensional transition metal electrocatalysts. Science 363, 870–874 (2019).

    Article  CAS  Google Scholar 

  24. Wang, C. et al. Synthesis of homogeneous Pt-bimetallic nanoparticles as highly efficient electrocatalysts. ACS Catal. 1, 1355–1359 (2011).

    Article  CAS  Google Scholar 

  25. He, D. S. et al. Ultrathin icosahedral Pt-enriched nanocage with excellent oxygen reduction reaction activity. J. Am. Chem. Soc. 138, 1494–1497 (2016).

    Article  CAS  Google Scholar 

  26. Pizzutilo, E. et al. The space confinement approach using hollow graphitic spheres to unveil activity and stability of Pt–Co nanocatalysts for PEMFC. Adv. Energy Mater. 7, 1700835 (2017).

    Article  CAS  Google Scholar 

  27. Mezzavilla, S. et al. Structure–activity–stability relationships for space-confined PtxNiy nanoparticles in the oxygen reduction reaction. ACS Catal. 6, 8058–8068 (2016).

    Article  CAS  Google Scholar 

  28. DOE Technical Targets for Polymer Electrolyte Membrane Fuel Cell Components https://energy.gov/eere/fuelcells/doe-technical-targets-polymer-electrolyte-membrane-fuel-cell-components (US DOE, 2016).

  29. Kodama, K., Nagai, T., Kuwaki, A., Jinnouchi, R. & Morimoto, Y. Challenges in applying highly active Pt-based nanostructured catalysts for oxygen reduction reactions to fuel cell vehicles. Nat. Nanotechnol. 16, 140–147 (2021).

    Article  CAS  Google Scholar 

  30. Weber, A. Z. & Kusoglu, A. Unexplained transport resistances for low-loaded fuel-cell catalyst layers. J. Mater. Chem. A 2, 17207–17211 (2014).

    Article  CAS  Google Scholar 

  31. Holby, E. F., Sheng, W., Shao-Horn, Y. & Morgan, D. Pt nanoparticle stability in PEM fuel cells: influence of particle size distribution and crossover hydrogen. Energy Environ. Sci. 2, 865–871 (2009).

    Article  CAS  Google Scholar 

  32. Borup, R. L. et al. Recent developments in catalyst-related PEM fuel cell durability. Curr. Opin. Electrochem. 21, 192–200 (2020).

    Article  CAS  Google Scholar 

  33. Tang, L., Li, X., Cammarata, R. C., Friesen, C. & Sieradzki, K. Electrochemical stability of elemental metal nanoparticles. J. Am. Chem. Soc. 132, 11722–11726 (2010).

    Article  CAS  Google Scholar 

  34. Tang, L. et al. Electrochemical stability of nanometer-scale Pt particles in acidic environments. J. Am. Chem. Soc. 132, 596–600 (2010).

    Article  CAS  Google Scholar 

  35. Du, L. et al. Low-PGM and PGM-free catalysts for proton exchange membrane fuel cells: stability challenges and material solutions. Adv. Mater. 33, 1908232 (2021).

    Article  CAS  Google Scholar 

  36. Han, B. et al. Record activity and stability of dealloyed bimetallic catalysts for proton exchange membrane fuel cells. Energy Environ. Sci. 8, 258–266 (2015).

    Article  CAS  Google Scholar 

  37. Braaten, J. P., Xu, X., Cai, Y., Kongkanand, A. & Litster, S. Contaminant cation effect on oxygen transport through the ionomers of polymer electrolyte membrane fuel cells. J. Electrochem. Soc. 166, F1337–F1343 (2019).

    Article  CAS  Google Scholar 

  38. Sulek, M., Adams, J., Kaberline, S., Ricketts, M. & Waldecker, J. R. In situ metal ion contamination and the effects on proton exchange membrane fuel cell performance. J. Power Sources 196, 8967–8972 (2011).

    Article  CAS  Google Scholar 

  39. Hoene, J. V., Charles, R. G. & Hickam, W. M. Thermal decomposition of metal acetylacetonates: mass spectrometer studies. J. Phys. Chem. 62, 1098–1101 (1958).

    Article  Google Scholar 

  40. Grimm, S. et al. Gas-phase aluminium acetylacetonate decomposition: revision of the current mechanism by VUV synchrotron radiation. Phys. Chem. Chem. Phys. 23, 15059–15075 (2021).

    Article  CAS  Google Scholar 

  41. Fei, L.-f et al. Direct observation of carbon nanostructure growth at liquid–solid interfaces. Chem. Commun. 50, 826–828 (2014).

    Article  CAS  Google Scholar 

  42. Picher, M., Lin, P. A., Gomez-Ballesteros, J. L., Balbuena, P. B. & Sharma, R. Nucleation of graphene and its conversion to single-walled carbon nanotubes. Nano Lett. 14, 6104–6108 (2014).

    Article  CAS  Google Scholar 

  43. Fan, H. et al. Dynamic state and active structure of Ni–Co catalyst in carbon nanofiber growth revealed by in situ transmission electron microscopy. ACS Nano 15, 17895–17906 (2021).

    Article  CAS  Google Scholar 

  44. Zhao, Z. et al. Tailoring a three-phase microenvironment for high-performance oxygen reduction reaction in proton exchange membrane fuel cells. Matter 3, 1774–1790 (2020).

    Article  Google Scholar 

  45. Cullen, D. A. et al. New roads and challenges for fuel cells in heavy-duty transportation. Nat. Energy 6, 462–474 (2021).

    Article  CAS  Google Scholar 

  46. Chong, L. et al. Ultralow-loading platinum–cobalt fuel cell catalysts derived from imidazolate frameworks. Science 362, 1276–1281 (2018).

    Article  CAS  Google Scholar 

  47. Jia, Q. et al. Improved oxygen reduction activity and durability of dealloyed PtCox catalysts for proton exchange membrane fuel cells: strain, ligand, and particle size effects. ACS Catal. 5, 176–186 (2015).

    Article  CAS  Google Scholar 

  48. Li, J. et al. Hard-magnet L10-CoPt nanoparticles advance fuel cell catalysis. Joule 3, 124–135 (2019).

    Article  CAS  Google Scholar 

  49. Papadias, D. D. et al. Durability of Pt–Co alloy polymer electrolyte fuel cell cathode catalysts under accelerated stress tests. J. Electrochem. Soc. 165, F3166–F3177 (2018).

    Article  CAS  Google Scholar 

  50. Slack, J. J. et al. Nanofiber fuel cell MEAs with a PtCo/C cathode. J. Electrochem. Soc. 166, F3202–F3209 (2019).

    Article  CAS  Google Scholar 

  51. Fuel Cell Technologies Office Multi-year Research, Development, and Demonstration Plan https://www.energy.gov/eere/fuelcells/downloads/fuel-cell-technologies-office-multi-year-research-development-and-22 (US DOE, 2017).

  52. Zhao, Z. et al. Pt-based nanocrystal for electrocatalytic oxygen reduction. Adv. Mater. 31, 1808115 (2019).

    Article  CAS  Google Scholar 

  53. Kleen, G. & Padgett, E. Durability-Adjusted Fuel Cell System Cost (US DOE, 2021).

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

    Article  CAS  Google Scholar 

  55. Garsany, Y., Atkinson, R. W., Gould, B. D. & Swider-Lyons, K. E. High power, low-Pt membrane electrode assemblies for proton exchange membrane fuel cells. J. Power Sources 408, 38–45 (2018).

    Article  CAS  Google Scholar 

  56. Papageorgopoulos, D. Fuel Cell R&D Overview (US DOE, 2019).

  57. Kongkanand, A. Highly Accessible Catalysts for Durable High Power Performance (US DOE, 2020).

  58. Stariha, S. et al. Recent advances in catalyst accelerated stress tests for polymer electrolyte membrane fuel cells. J. Electrochem. Soc. 165, F492–F501 (2018).

    Article  CAS  Google Scholar 

  59. Zhao, Z. et al. Tailoring a three-phase microenvironment for high-performance oxygen reduction reaction in proton exchange membrane fuel cells. Matter 3, 1774–1790 (2020).

    Article  Google Scholar 

  60. Huang, P. Y. et al. Grains and grain boundaries in single-layer graphene atomic patchwork quilts. Nature 469, 389–392 (2011).

    Article  CAS  Google Scholar 

  61. Stariha, S. et al. Recent advances in catalyst accelerated stress tests for polymer electrolyte membrane fuel cells. J. Electrochem. Soc. 165, F492–F501 (2018).

    Article  CAS  Google Scholar 

  62. Garrick, T. R., Moylan, T. E., Carpenter, M. K. & Kongkanand, A. Electrochemically active surface area measurement of aged Pt alloy catalysts in PEM fuel cells by CO stripping. J. Electrochem. Soc. 164, F55–F59 (2016).

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

  64. Garsany, Y., Atkinson, R. W., Gould, B. D. & Swider-Lyons, K. E. High power, low-Pt membrane electrode assemblies for proton exchange membrane fuel cells. J. Power Sources 408, 38–45 (2018).

    Article  CAS  Google Scholar 

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

    Article  CAS  Google Scholar 

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Acknowledgements

Y.H., X.D., Z.Z., Z.L., A.Z., W.X. and B.P. acknowledge the Office of Naval Research (ONR) grant N00014-18-1-2155. Y.H., Z.Z., Z.L. and A.Z. acknowledge the Defense University Research Instrumentation Program (DURIP) grant N00014-18-1-2271. X.Y. and X.P. acknowledge the DOE, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering grant DE-SC0014430. We acknowledge the use of facilities and instrumentation at the UC Irvine Materials Research Institute (IMRI), which is supported in part by the National Science Foundation through the UC Irvine Materials Research Science and Engineering Center (DMR-2011967). We also acknowledge assistance in additional electron microscopy characterizations by C. Wang and L. Han (UC Irvine). C. Wang, L. Han and H.L.X. acknowledge National Science Foundation grant CHE-1900401 and the TEM resources of the Center for Functional Nanomaterials (CFN), which is a US DOE Office of Science User Facility at Brookhaven National Laboratory under contract no. DE-SC0012704.

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Contributions

For the experimental design and execution, the synthesis of the electrocatalysts, structural characterization, MEA fabrication and electrochemical testing were carried out by Z.Z., Z.L., A.Z., W.X. and B.P., the S/TEM and EDS characterizations by X.Y. and Z.Z. Supervision was carried out by Y.H. (conceptualization, project design, syntheses and evaluation of the catalysts), X.P. (STEM and EELS) and H.L.X. (additional EM studies). The original draft was written by Z.Z., X.D. and Y.H., and edited by Z.Z., Z.L., X.D. and Y.H.

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Correspondence to Yu Huang.

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Patent application filed on the catalyst development as US Provisional Application no. 63/222,293 by the UCLA inventors: Y.H., X.D., Z.Z. and Z.L.; the remaining authors declare no competing interests.

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Nature Nanotechnology thanks Yadong Yin and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Zhao, Z., Liu, Z., Zhang, A. et al. Graphene-nanopocket-encaged PtCo nanocatalysts for highly durable fuel cell operation under demanding ultralow-Pt-loading conditions. Nat. Nanotechnol. 17, 968–975 (2022). https://doi.org/10.1038/s41565-022-01170-9

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