Mesoporous Textured Fe-N-C Electrocatalysts as Highly Efficient Cathodes for Proton Exchange Membrane Fuel Cells

Akula, Srinu; Mooste, Marek; Zulevi, Barr; McKinney, Sam; Kikas, Arvo; Piirsoo, Helle-Mai; Rahn, Mihkel; Tamm, Aile; Kisand, Vambola; Serov, Alexey; Creel, Erin B.; Cullen, David A.; Neyerlin, Kenneth C.; Wang, Hao; Odgaard, Madeleine; Reshetenko, Tatyana; Tammeveski, Kaido

doi:10.1016/j.jpowsour.2021.230819

Mesoporous Textured Fe-N-C Electrocatalysts as Highly Efficient Cathodes for Proton Exchange Membrane Fuel Cells

Journal Article · 28 November 2021 · Journal of Power Sources

DOI:https://doi.org/10.1016/j.jpowsour.2021.230819· OSTI ID:1836660

Akula, Srinu; Mooste, Marek; Zulevi, Barr; McKinney, Sam; Kikas, Arvo; Piirsoo, Helle-Mai; Rahn, Mihkel; Tamm, Aile; Kisand, Vambola; Serov, Alexey; Creel, Erin B.; Cullen, David A.; Neyerlin, Kenneth C.; Wang, Hao; Odgaard, Madeleine; Reshetenko, Tatyana; Tammeveski, Kaido

A new platinum group metal (PGM)-free proton exchange membrane fuel cell (PEMFC) cathode catalyst materials, synthesized using the VariPore™ method by Pajarito Powder, LLC, are characterized for their structure and activity. The physico-chemical analysis of the iron-nitrogen-carbon (Fe-N-C) electrocatalysts show mesoporous carbon material effectively doped with iron and nitrogen. The materials have an average pore size of 7-8 nm and high specific surface area. The Fe-N-C catalysts exhibit good oxygen reduction reaction (ORR) activity in 0.5 M H2SO4 electrolyte with high half-wave potential and sustainable electrochemical stability over 10,000 repeated potential cycles with insignificant losses in their activities. As cathode catalysts in a PEMFC, the Fe-N-C materials deliver remarkably good fuel cell performance at low overpotential approaching that of the commercial Pt catalyst. The high ORR electrocatalytic activity of these Fe-N-C catalysts is credited to the synergy between nitrogen-moieties, specifically pyrrolic-N, pyridinic-N, and graphitic-N, and iron in addition to the high mesoporosity that facilitate an effective reaction path in boosting the electrocatalytic activity and stability.

Research Organization:: National Renewable Energy Lab. (NREL), Golden, CO (United States)

Sponsoring Organization:: USDOE Office of Energy Efficiency and Renewable Energy (EERE)

DOE Contract Number:: AC36-08GO28308

OSTI ID:: 1836660

Report Number(s):: NREL/JA-5900-81696; MainId:82469; UUID:79b8b32f-a828-4b35-a667-4e08cdaac3b8; MainAdminID:63459

Journal Information:: Journal of Power Sources, Vol. 520

Country of Publication:: United States

Language:: English

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Mesoporous textured Fe-N-C electrocatalysts as highly efficient cathodes for proton exchange membrane fuel cells

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Mesoporous Textured Fe-N-C Electrocatalysts as Highly Efficient Cathodes for Proton Exchange Membrane Fuel Cells

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