Revealing Isolated M-N₃ C₁ Active Sites for Efficient Collaborative Oxygen Reduction Catalysis

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Single atom catalysts (SACs) are crucial for oxygen reduction reactions (ORR) in energy technologies.
• Optimizing SAC active site structures is key to enhancing catalytic performance.
• Limited exploration of highly active SAC structures hinders progress.

Purpose of the Study:

• To investigate the oxygen reduction catalysis of SACs featuring M-N3C1 sites.
• To explore the structure-activity relationship of atomically dispersed transition metals (Fe, Co, Cu) in nitrogenated carbon nanosheets.

Main Methods:

• Combined experimental and theoretical study.
• Synthesis and characterization of SACs with M-N3C1 active sites.
• Electrocatalytic testing in acidic and alkaline media.
• Density Functional Theory (DFT) calculations.

Main Results:

• SACs with M-N3C1 sites demonstrated significant ORR catalytic activities.
• Activity trend observed: Fe-N3C1 > Co-N3C1 > Cu-N3C1.
• Theoretical calculations revealed synergistic effects between metal (M) and carbon (C) atoms.

Conclusions:

• The M-N3C1 site structure facilitates efficient dual-site oxygen reduction.
• Atomic arrangement and electronic interactions (d/p orbital coupling) enhance catalytic activity.
• These findings offer insights for designing advanced SACs for renewable energy applications.