Abstract
The prohibitive cost and scarcity of the noble-metal catalysts needed for catalysing the oxygen reduction reaction (ORR) in fuel cells and metal-air batteries limit the commercialization of these clean-energy technologies. Identifying a catalyst design principle that links material properties to the catalytic activity can accelerate the search for highly active and abundant transition-metal-oxide catalysts to replace platinum. Here, we demonstrate that the ORR activity for oxide catalysts primarily correlates to σ*-orbital (eg) occupation and the extent of B-site transition-metal-oxygen covalency, which serves as a secondary activity descriptor. Our findings reflect the critical influences of the σ * orbital and metal-oxygen covalency on the competition between O2 2-/OH- displacement and OH- regeneration on surface transition-metal ions as the rate-limiting steps of the ORR, and thus highlight the importance of electronic structure in controlling oxide catalytic activity.
Originalsprache | Englisch |
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Seiten (von - bis) | 546-550 |
Seitenumfang | 5 |
Fachzeitschrift | Nature Chemistry |
Jahrgang | 3 |
Ausgabenummer | 7 |
DOIs | |
Publikationsstatus | Veröffentlicht - Mai 2011 |