P-block single-metal-site tin/nitrogen-doped carbon fuel cell cathode catalyst for oxygen reduction reaction

ABSTRACT This contribution reports the discovery and analysis of a _p_-block Sn-based catalyst for the electroreduction of molecular oxygen in acidic conditions at fuel cell cathodes; the

catalyst is free of platinum-group metals and contains single-metal-atom actives sites coordinated by nitrogen. The prepared SnNC catalysts meet and exceed state-of-the-art FeNC catalysts in

terms of intrinsic catalytic turn-over frequency and hydrogen–air fuel cell power density. The SnNC-NH3 catalysts displayed a 40–50% higher current density than FeNC-NH3 at cell voltages

below 0.7 V. Additional benefits include a highly favourable selectivity for the four-electron reduction pathway and a Fenton-inactive character of Sn. A range of analytical techniques

combined with density functional theory calculations indicate that stannic Sn(iv)N_x_ single-metal sites with moderate oxygen chemisorption properties and low pyridinic N coordination

numbers act as catalytically active moieties. The superior proton-exchange membrane fuel cell performance of SnNC cathode catalysts under realistic, hydrogen–air fuel cell conditions,

particularly after NH3 activation treatment, makes them a promising alternative to today’s state-of-the-art Fe-based catalysts. Access through your institution Buy or subscribe This is a

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EXCHANGE MEMBRANE FUEL CELL CATHODE BY CHEMICAL VAPOR MODIFICATION Article Open access 17 May 2024 PERFORMANCE ENHANCEMENT AND DEGRADATION MECHANISM IDENTIFICATION OF A SINGLE-ATOM CO–N–C

CATALYST FOR PROTON EXCHANGE MEMBRANE FUEL CELLS Article 30 November 2020 CO(CN)3 CATALYSTS WITH WELL-DEFINED COORDINATION STRUCTURE FOR THE OXYGEN REDUCTION REACTION Article 16 November

2023 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

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covalence breaks adsorption-energy scaling relations and solvation restores them. _Chem. Sci._ 8, 124–130 (2017). CAS  Google Scholar  Download references ACKNOWLEDGEMENTS We thank S. Dresp,

J. Li, H. Tian, S. Li, A. Thomas and T. Reier for assistance with RRDE, XPS and CO-pulse chemisorption experiments; S. Kühl for help with the TEM experiment; and R. Krähnert, H. Wang and D.

Bernsmeier for help with the nitrogen physisorption experiments. We also thank Helmholtz-Zentrum Berlin (Bessy II) for allocation of synchrotron radiation beamtime. Aberration-corrected

STEM-EELS was conducted at the Center for Nanophase Materials Sciences, which is a US Department of Energy Office of Science User Facility. L.S. and J.R. thank the Danish National Research

Foundation for support via grant DNRF 149 and Innovation Fund Denmark for funding through the ProActivE Project no. 5160-00003B. This project received financial support from the BMBF via

contract 05K16RD1 and by the Graduate School of Excellence Energy Science and Engineering (GRC1070). Research leading to some of these results has received funding from the Fuel Cells and

Hydrogen 2 Joint Undertaking under grant agreement no. 779366, CRESCENDO. This Joint Undertaking receives support from the European Union’s Horizon 2020 research and innovation programme,

Hydrogen Europe and Hydrogen Europe Research. F.L. and P.S. acknowledge partial funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany’s Excellence

Strategy—EXC 2008/1—390540038 (zum Teil gefördert durch die DFG im Rahmen der Exzellenzstrategie des Bundes und der Länder—EXC 2008/1—390540038). F.L. also thanks the China Scholarship

Council (CSC) for financial support. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Department of Chemistry, The Electrochemical Energy, Catalysis and Material Science Laboratory, Chemical

Engineering Division, Technical University Berlin, Berlin, Germany Fang Luo, Ju Wen, Fabio Dionigi & Peter Strasser * ICGM, Univ. Montpellier, CNRS, ENSCM, Montpellier, France Aaron Roy,

 Moulay Tahar Sougrati, Ismail Can Oguz, Tzonka Mineva & Frédéric Jaouen * Nano-Science Center, Department of Chemistry, University Copenhagen, Copenhagen, Denmark Luca Silvioli & 

Jan Rossmeisl * Seaborg Technologies, Copenhagen, Denmark Luca Silvioli * Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN, USA David A. Cullen *

Synchrotron SOLEIL, L’orme des Merisiers, BP 48, Saint Aubin, Gif-sur-Yvette, France Andrea Zitolo * The Fritz-Haber-Institute der Max-Planck-Gesellschaft, Inorganic Chemistry-Electronic

Structure Group, Berlin, Germany Detre Teschner * Department of Heterogeneous Reaction, Max-Planck-Institute for Chemical Energy Conversion, Berlin, Germany Detre Teschner * Department of

Chemistry and Department of Materials and Earth Sciences, Graduate School of Excellence Energy Science and Engineering, Technical University Darmstadt, Darmstadt, Germany Stephan Wagner 

& Ulrike I. Kramm Authors * Fang Luo View author publications You can also search for this author inPubMed Google Scholar * Aaron Roy View author publications You can also search for

this author inPubMed Google Scholar * Luca Silvioli View author publications You can also search for this author inPubMed Google Scholar * David A. Cullen View author publications You can

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Mineva View author publications You can also search for this author inPubMed Google Scholar * Detre Teschner View author publications You can also search for this author inPubMed Google

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Google Scholar * Fabio Dionigi View author publications You can also search for this author inPubMed Google Scholar * Ulrike I. Kramm View author publications You can also search for this

author inPubMed Google Scholar * Jan Rossmeisl View author publications You can also search for this author inPubMed Google Scholar * Frédéric Jaouen View author publications You can also

search for this author inPubMed Google Scholar * Peter Strasser View author publications You can also search for this author inPubMed Google Scholar CONTRIBUTIONS F.L., P.S. and F.J.

conceived, designed and coordinated the study. F.L. carried out the materials synthesis, characterization and electrochemical evaluations. A.R. performed the membrane electrode assembly,

D.A.C. performed STEM/EELS, A.Z. performed Sn K-edge EXAFS/XANES, M.T.S., I.C.O., T.M., S.W. and U.I.K. performed Mössbauer spectroscopy, and D.T. performed XPS and Fe L-edge XAS

experimental work. L.S. and J.R. performed the DFT computational study. J.W. and F. D. participated in the discussion of the electrochemical results section. All authors discussed the

results and commented on the manuscript. F.L. wrote the manuscript with the contribution of all co-authors. CORRESPONDING AUTHORS Correspondence to Jan Rossmeisl, Frédéric Jaouen or Peter

Strasser. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. ADDITIONAL INFORMATION PUBLISHER’S NOTE Springer Nature remains neutral with regard to

jurisdictional claims in published maps and institutional affiliations. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary methods, Notes 0–2, Figs. 1–15 and Tables 1–15.

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ARTICLE Luo, F., Roy, A., Silvioli, L. _et al._ _P_-block single-metal-site tin/nitrogen-doped carbon fuel cell cathode catalyst for oxygen reduction reaction. _Nat. Mater._ 19, 1215–1223

(2020). https://doi.org/10.1038/s41563-020-0717-5 Download citation * Received: 28 February 2020 * Accepted: 25 May 2020 * Published: 13 July 2020 * Issue Date: November 2020 * DOI:

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