Cu-O-In Bridge Engineering in Cu₂O/In₂O₃ Nanowires for Efficient CO₂-to-CO Electroreduction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Modulating the d-band center (εd) is key for electrocatalytic activity.
• Precise regulation of εd for CO2 electroreduction (eCO2R) to CO remains challenging.
• Heterostructured catalysts offer potential for enhanced performance.

Purpose of the Study:

• To develop a catalyst with tunable εd for efficient eCO2R to CO.
• To investigate the role of Cu-O-In bridges in regulating εd.
• To achieve high CO selectivity, production rate, and stability.

Main Methods:

• Fabrication of a heterostructured catalyst: In2O3-incorporated 3D nanowire copper foam (Cu2O/In2O3@CF).
• Electrochemical characterization to assess CO2 reduction performance (Faradaic efficiency, production rate).
• In situ spectroscopy (Raman, FTIR) and Density Functional Theory (DFT) calculations to understand the mechanism.

Main Results:

• Optimized Cu2O/In2O3@CF achieved >90% CO Faradaic efficiency over a broad potential range (-0.47 to -0.87 V vs. RHE).
• Peak CO Faradaic efficiency reached 95.8% at -0.67 V (vs. RHE) with a high production rate of 1035.3 µmol cm⁻² h⁻¹.
• The catalyst demonstrated stable operation for over 130 hours.
• Cu-O-In bridges at the Cu2O/In2O3 heterointerface facilitated charge redistribution, optimizing εd for eCO2R intermediates.

Conclusions:

• The Cu2O/In2O3@CF catalyst effectively tunes the d-band center via Cu-O-In bridges for enhanced eCO2R.
• Synergistic design of oxide-oxide heterointerfaces and 1D nanowire architecture is a promising strategy for CO2 electroreduction.
• This work provides a new pathway for designing efficient electrocatalysts for CO2 conversion.