Quasi-Copper-Mers Enable High-Performance Catalysis for CO₂ Reduction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Rising atmospheric carbon dioxide (CO2) necessitates effective mitigation strategies.
• Electrochemical CO2 reduction is a promising pathway for converting CO2 into valuable products.
• A significant challenge is the lack of highly active and selective electrocatalysts.

Purpose of the Study:

• To investigate a novel class of electrocatalysts, quasi-copper-mers, for CO2 reduction.
• To evaluate the performance of quasi-copper-monomers, -dimers, and -trimers.
• To understand the mechanisms underlying their electrocatalytic activity and selectivity.

Main Methods:

• Synthesis of quasi-copper-monomers, -dimers, and -trimers on a graphene-like substrate.
• Experimental characterization of synthesized electrocatalysts.
• Density Functional Theory (DFT) calculations to analyze atomic structures and reaction mechanisms.

Main Results:

• Quasi-copper-trimers exhibited higher activity for CO2 to CO conversion compared to dimers and monomers.
• Quasi-copper-trimers showed superior selectivity, suppressing the hydrogen evolution reaction (HER).
• DFT calculations supported experimental findings and revealed the origin of the trimer's enhanced performance.

Conclusions:

• Quasi-copper-mers, particularly trimers, represent a new class of effective electrocatalysts for CO2 reduction.
• The CuN4 motif, not individual Cu atoms, is the key building block for high performance.
• This work presents a novel strategy for designing high-activity and high-selectivity electrocatalysts for CO2 conversion.