A Structure-Defined Cu(I) Dual-Atom Catalyst with a Cu₂N₆ Motif in a Metal-Organic Framework for CO Electroreduction

Area of Science:

• Catalysis
• Materials Science
• Electrochemistry

Background:

• Carbon monoxide (CO) electroreduction is crucial for producing multi-carbon (C₂₊) chemicals and achieving carbon neutrality.
• Optimizing C₂₊ selectivity requires precise control over catalytic site arrangement for CO adsorption and coupling.
• Existing catalysts often struggle with efficiency and selectivity in CO electroreduction.

Purpose of the Study:

• To develop a structurally defined copper dual-atom catalyst (DAC) for enhanced CO electroreduction.
• To investigate the relationship between catalyst structure, CO adsorption, and C₂₊ product formation.
• To achieve high Faradaic efficiency (FE) and partial current density for C₂₊ products.

Main Methods:

• Synthesis of a Cu(I) DAC embedded in a metal-organic framework (MOF) via thermal transformation.
• Single-crystal X-ray diffraction (SCD) for precise structural characterization of the Cu₂N₆ motifs.
• Electrochemical testing to evaluate catalyst performance (FE, partial current density).
• In situ spectroscopy and density functional theory (DFT) calculations to elucidate reaction mechanisms.

Main Results:

• A well-defined Cu(I) DAC with a Cu-Cu distance of 3.6 Å was synthesized and structurally confirmed.
• The catalyst achieved a 72% FE for C₂₊ products at -430 mA cm^-2 and a maximum C₂₊ FE of 86% at -200 mA cm^-2.
• DFT and spectroscopy revealed that paired Cu nodes stabilize C₂ intermediates through specific binding, enhancing performance.

Conclusions:

• The developed Cu(I) DAC in a MOF offers a highly efficient and selective pathway for CO electroreduction to C₂₊ products.
• Precise control over the spatial arrangement of catalytic sites is key to improving CO coupling efficiency.
• This work provides a promising strategy for designing advanced catalysts for sustainable chemical synthesis.