Edge-Rich Fe-N4 Active Sites in Defective Carbon for Oxygen Reduction Catalysis
© 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
| Veröffentlicht in: | Advanced materials (Deerfield Beach, Fla.). - 1998. - 32(2020), 16 vom: 15. Apr., Seite e2000966 |
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| 1. Verfasser: | |
| Weitere Verfasser: | , , , , , , , , , , |
| Format: | Online-Aufsatz |
| Sprache: | English |
| Veröffentlicht: |
2020
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| Zugriff auf das übergeordnete Werk: | Advanced materials (Deerfield Beach, Fla.) |
| Schlagworte: | Journal Article FeN4 active sites fuel cells oxygen reduction reaction |
| Zusammenfassung: | © 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim. Controllably constructing nitrogen-modified divacancies (ND) in carbon substrates to immobilize atomic Fe species and unveiling the advantageous configuration is still challenging, but indispensable for attaining optimal Fe-N-C catalysts for the oxygen reduction reaction (ORR). Herein, a fundamental investigation of unfolding intrinsically superior edge-ND trapped atomic Fe motifs (e-ND-Fe) relative to an intact center model (c-ND-Fe) in ORR electrocatalysis is reported. Density functional theory calculations reveal that local electronic redistribution and bandgap shrinkage for e-ND-Fe endow it with a lower free-energy barrier toward direct four-electron ORR. Inspired by this, a series of atomic Fe catalysts with adjustable ND-Fe coordination are synthesized, which verify that ORR performance highly depends on the concentration of e-ND-Fe species. Remarkably, the best e-ND-Fe catalyst delivers a favorable kinetic current density and halfwave potential that can be comparable to benchmark Pt-C under acidic conditions. This work will guide to develop highly active atomic metal catalysts through rational defect engineering |
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| Beschreibung: | Date Revised 30.09.2020 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1521-4095 |
| DOI: | 10.1002/adma.202000966 |