Inhibiting Demetalation of FeâNâC via Mn Sites for Efficient Oxygen Reduction Reaction in Zinc-Air Batteries.
Adv Mater
; 36(32): e2405763, 2024 Aug.
Article
em En
| MEDLINE
| ID: mdl-38809945
ABSTRACT
Demetalation caused by the electrochemical dissolution of metallic Fe atoms is a major challenge for the practical application of FeâNâC catalysts. Herein, an efficient single metallic Mn active site is constructed to improve the strength of the FeâN bond, inhibiting the demetalation effect of FeâNâC. Mn acts as an electron donor inducing more delocalized electrons to reduce the oxidation state of Fe by increasing the electron density, thereby enhancing the FeâN bond and inhibiting the electrochemical dissolution of Fe. The oxygen reduction reaction pathway for the dissociation of FeâMn dual sites can overcome the high energy barriers to direct OâO bond dissociation and modulate the electronic states of FeâN4 sites. The resulting FeMnâNâC exhibits excellent ORR activity with a high half-wave potential of 0.92 V in alkaline electrolytes. FeMnâNâC as a cathode catalyst for Zn-air batteries has a cycle stability of 700 h at 25 °C and a long cycle stability of more than 210 h under extremely cold conditions at -40 °C. These findings contribute to the development of efficient and stable metal-nitrogen-carbon catalysts for various energy devices.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article