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Abstract Carbon‐supported nitrogen‐coordinated single‐metal site catalysts (i.e., M−N−C, M: Fe, Co, or Ni) are active for the electrochemical CO2reduction reaction (CO2RR) to CO. Further improving their intrinsic activity and selectivity by tuning their N−M bond structures and coordination is limited. Herein, we expand the coordination environments of M−N−C catalysts by designing dual‐metal active sites. The Ni‐Fe catalyst exhibited the most efficient CO2RR activity and promising stability compared to other combinations. Advanced structural characterization and theoretical prediction suggest that the most active N‐coordinated dual‐metal site configurations are 2N‐bridged (Fe‐Ni)N6, in which FeN4and NiN4moieties are shared with two N atoms. Two metals (i.e., Fe and Ni) in the dual‐metal site likely generate a synergy to enable more optimal *COOH adsorption and *CO desorption than single‐metal sites (FeN4or NiN4) with improved intrinsic catalytic activity and selectivity.
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Reductant composition influences the coordination of atomically dispersed Rh on anatase TiO 2
Atomically dispersed noble metal catalysts have received recent interest, although the coordination of the metal to the support and how this is influenced by pre-treatment have not often been elucidated. We combine CO FTIR-TPD and DFT to distinguish how catalyst reduction via CO or H 2 influence the local metal coordination and molecular desorption processes.
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- Award ID(s):
- 1804128
- PAR ID:
- 10190620
- Date Published:
- Journal Name:
- Catalysis Science & Technology
- Volume:
- 10
- Issue:
- 6
- ISSN:
- 2044-4753
- Page Range / eLocation ID:
- 1597 to 1601
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D0CY00146E
