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Updated: Jul 10, 2026
10:57
Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Strength of Interlayer Metal-Metal Coupling as Key Active Site Configuration and Atomic Descriptor for Single-Atom
Liangliang Xu1,2, Jiankang Wang1, Hanxu Yao3
1Department of Chemistry, The University of Hong Kong, Hong Kong SAR 999077, China.
Journal of the American Chemical Society
|July 9, 2026
Summary
Researchers identified a stacked bilayer metal-metal coupling (MMC) configuration as a key active site in single-atom catalysts (SACs) for oxygen reduction reactions (ORR). This finding reconciles theoretical predictions with experimental data, guiding the rational design of efficient electrocatalysts.
Area of Science:
- Materials Science
- Electrochemistry
- Computational Chemistry
Background:
- Single-atom catalysts (SACs) offer high efficiency but their active site configurations are not fully understood.
- Layered Fe-N-C catalysts show a significant gap between theoretical and experimental oxygen reduction reaction (ORR) activity.
- Predictive modeling of SACs is hindered by incomplete knowledge of active site regulation.
Purpose of the Study:
- To identify the critical active-site configuration in layered Fe-N-C catalysts for ORR.
- To reconcile discrepancies between theoretical predictions and experimental ORR activity in SACs.
- To establish a framework for rational catalyst design and predictive theory.
Main Methods:
- X-ray absorption fine structure (XAFS) observations.
- Density functional theory (DFT) simulations and machine learning.
- Synthesis and experimental validation of molecular catalysts.
Main Results:
- A stacked bilayer metal-metal coupling (MMC) configuration was identified as a crucial active site.
- A computational model within the standard computational hydrogen electrode (CHE) framework accurately reproduced experimental ORR activity.
- Metal-metal coupling strength was quantified, correlating with catalytic activity and guiding modeling strategy selection.
- Local electronic-structure descriptors were identified for quantitative structure-activity relationships.
- Experimental synthesis validated the bilayer MMC motif's role in ORR.
Conclusions:
- The stacked bilayer MMC configuration is a key active site for ORR in Fe-N-C catalysts.
- Physically faithful active-site modeling is essential for predictive electrocatalysis theory.
- This work provides a pathway for the rational design of highly efficient SACs for ORR and other electrocatalytic applications.
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