Regulating Spin Polarization via Axial Nitrogen Traction at Fe-N5 Sites Enhanced Electrocatalytic CO2 Reduction for Zn-CO2 Batteries.
Angew Chem Int Ed Engl
; : e202406030, 2024 Jul 17.
Article
em En
| MEDLINE
| ID: mdl-39020457
ABSTRACT
Single Fe sites have been explored as promising catalysts for the CO2 reduction reaction to value-added CO. Herein, we introduce a novel molten salt synthesis strategy for developing axial nitrogen-coordinated Fe-N5 sites on ultrathin defect-rich carbon nanosheets, aiming to modulate the reaction pathway precisely. This distinctive architecture weakens the spin polarization at the Fe sites, promoting a dynamic equilibrium of activated intermediates and facilitating the balance between *COOH formation and *CO desorption at the active Fe site. Notably, the synthesized FeN5, supported on defect-rich in nitrogen-doped carbon (FeN5@DNC), exhibits superior performance in CO2RR, achieving a Faraday efficiency of 99% for CO production (-0.4 V vs. RHE) in an H-cell, and maintaining a Faraday efficiency of 98% at a current density of 270 mA cm-2 (-1.0 V vs. RHE) in the flow cell. Furthermore, the FeN5@DNC catalyst is assembled as a reversible Zn-CO2 battery with a cycle durability of 24 hours. In-situ IR spectroscopy and density functional theory (DFT) calculations reveal that the axial N coordination traction induces a transformation in the crystal field and local symmetry, therefore weakening the spin polarization of the central Fe atom and lowering the energy barrier for *CO desorption.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Angew Chem Int Ed Engl
Ano de publicação:
2024
Tipo de documento:
Article
País de afiliação:
China