Intermediate-regulated dynamic restructuring at Ag-Cu biphasic interface enables selective CO₂ electroreduction to...

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Bimetallic heterostructures enhance selectivity in carbon dioxide (CO2) electroreduction to multi-carbon (C2+) products.
• Understanding interfacial structures during electrolysis is key to controlling reaction pathways but remains challenging.

Purpose of the Study:

• To investigate the relationship between interfacial structure and product selectivity in a well-defined Ag-Cu biphasic heterostructure for CO2 electroreduction.
• To elucidate the mechanism of structure evolution and its impact on C2+ product formation.

Main Methods:

• Fabrication of a tunable Ag-Cu biphasic heterostructure.
• Electrochemical characterization of CO2 electroreduction performance.
• In-situ/operando analysis to probe interfacial restructuring and intermediate formation.

Main Results:

• Cu-rich interfaces favor ethylene production, while increasing Ag content shifts selectivity towards alcohols and then CO.
• A *CO intermediate-regulated restructuring mechanism was identified, involving Cu atom migration onto Ag surfaces.
• Altered interfacial oxyphilicity due to restructuring dictates CO2 hydrogenation energetics and C2+ product distribution.

Conclusions:

• The evolving interfacial structure in Ag-Cu heterostructures directly correlates with distinct C2+ product pathways.
• This work provides design principles for developing bimetallic electrocatalysts with enhanced and selective C2+ yields from CO2 reduction.