Confined Fe-Cu Clusters as Sub-Nanometer Reactors for Efficiently Regulating the Electrochemical Nitrogen Reduction...

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical nitrogen reduction reaction (NRR) is a sustainable method for ammonia synthesis.
• Nonprecious-metal and single-atom catalysts are key for NRR, but achieving atomic-scale cooperation is difficult.
• Existing catalysts face challenges in regulating active sites due to large distances, hindering cooperative effects.

Purpose of the Study:

• To design and synthesize novel catalysts for enhanced electrochemical nitrogen reduction reaction (NRR).
• To investigate the synergistic effects of multiple metal atoms confined within a sub-nanometer scale.
• To explore new strategies for manipulating catalyst active centers at the atomic level for ammonia synthesis.

Main Methods:

• Utilizing graphitic carbon nitride with regular surface cavities as "subnano reactors".
• Precisely confining multiple iron (Fe) and copper (Cu) atoms within these cavities.
• Employing first-principle simulations to understand the catalytic mechanism.

Main Results:

• The confined Fe-Cu multi-atom catalyst exhibited significantly enhanced NRR performance compared to single-metal catalysts.
• Ammonia yield nearly doubled, and Faradic efficiency increased by 54% to 34%.
• First-principle simulations revealed synergistic effects due to Fe-Cu coordination, improving N2 absorption and electron transfer.

Conclusions:

• Confined multi-atom catalysts in subnano reactors offer a promising strategy for efficient ammonia synthesis.
• The synergistic interaction between Fe and Cu atoms at the sub-nanometer scale is crucial for enhanced NRR performance.
• This work presents a new paradigm for catalyst design by manipulating active centers at the atomic level.