Defective Indium/Indium Oxide Heterostructures for Highly Selective Carbon Dioxide Electrocatalysis

Area of Science:

• Electrochemistry
• Materials Science
• Catalysis

Background:

• Electrochemical carbon dioxide (CO2) reduction is crucial for CO2 utilization.
• Developing efficient, selective, and cost-effective electrocatalysts is essential for large-scale CO2 reduction applications.
• Current electrocatalysts often face challenges with activity, selectivity, and stability.

Purpose of the Study:

• To develop novel electrocatalysts for selective CO2 reduction to C1 products.
• To investigate the performance of defective indium/indium oxide heterostructures for CO2 electroreduction.
• To understand the synergistic effects within the heterostructure for enhanced catalytic activity and selectivity.

Main Methods:

• Fabrication of defective indium/indium oxide heterostructures.
• Electrochemical characterization of CO2 reduction in aqueous media across a broad potential range (-0.7 to -1.2 V vs RHE).
• Analysis of product selectivity, faradaic efficiency, activity, and durability.

Main Results:

• The defective In/In oxide heterostructures demonstrated high selectivity for CO2 electroreduction to C1 products, primarily formate (up to 93%).
• Achieved near 100% faradaic efficiency for CO2 reduction.
• Exhibited excellent catalytic activity (up to 50.8 mA cm-2) and durability (>25 h) in aqueous media.

Conclusions:

• Defective In/In oxide heterostructures are highly effective electrocatalysts for selective CO2-to-formate conversion.
• The synergy between metallic In (facilitating formate production) and In oxide (suppressing hydrogen evolution) enhances performance.
• Integrating functional components and defects into heterostructures is a promising strategy for advancing CO2 electrocatalysis.