Facile and Stable CuInO₂ Nanoparticles for Efficient Electrochemical CO₂ Reduction

Area of Science:

• Materials Science
• Electrochemistry
• Catalysis

Background:

• Electrochemical carbon dioxide reduction reaction (e-CO2RR) is crucial for sustainable energy.
• Developing selective and stable electrocatalysts for e-CO2RR remains a significant challenge.
• Copper-based materials show promise but require further optimization for selectivity and durability.

Purpose of the Study:

• To design and synthesize a novel Cu-CuInO2 composite electrocatalyst.
• To investigate the catalyst's performance in the e-CO2RR.
• To understand the structure-activity relationship for enhanced CO2 conversion.

Main Methods:

• Electrochemical deposition of indium onto CuCl-decorated Cu foil to form Cu-CuInO2 composite.
• Electrocatalytic performance testing for CO2 reduction.
• Systematical characterizations (e.g., XRD, XPS, SEM, TEM) to analyze catalyst structure and composition.
• First-principles calculations to elucidate reaction mechanisms and energy barriers.

Main Results:

• The Cu-CuInO2 composite catalyst exhibited superior selectivity towards CO production.
• Maximal Faraday efficiency of 89% for CO was achieved at -0.9 V vs RHE.
• The catalyst maintained impressive stability for over 27 hours with >76% Faraday efficiency retention.
• Characterizations confirmed the presence of stable Cu0/Cu+ states and attributed performance to CuInO2 nanoparticles.
• Theoretical calculations supported experimental findings, indicating CuInO2(012) favors CO generation and suppresses hydrogen evolution.

Conclusions:

• The developed Cu-CuInO2 composite is a highly selective and stable electrocatalyst for e-CO2RR.
• CuInO2 nanoparticles play a key role in enhancing catalytic performance.
• The catalyst offers a promising pathway for efficient CO2 conversion into valuable products.