Enrichment Strategies for Efficient CO₂ Electroreduction in Acidic Electrolytes

Area of Science:

• Electrochemistry
• Catalysis
• Environmental Science

Background:

• Electrochemical CO2 reduction (CO2 RR) is key for carbon neutrality, but carbonate formation in neutral/alkaline media limits efficiency.
• Acidic CO2 RR circumvents carbonate issues but suffers from competing hydrogen evolution reaction (HER), reducing activity and selectivity.
• Enhancing CO2 and intermediate concentrations at the catalyst surface is crucial for improving CO2 RR performance.

Purpose of the Study:

• To review the catalytic mechanisms and challenges of CO2 RR.
• To summarize progress in CO2 enrichment strategies for acidic CO2 RR.
• To provide insights into future directions for acidic CO2 RR.

Main Methods:

• Review of existing literature on CO2 RR mechanisms and challenges.
• Analysis of enrichment strategies including catalyst design, electrolyte regulation, and electrolyzer optimization.
• Discussion of future perspectives for enhancing acidic CO2 RR.

Main Results:

• Identified carbonate formation as a major drawback in neutral/alkaline CO2 RR.
• Highlighted the trade-off between HER suppression and CO2 RR activity/selectivity in acidic media.
• Demonstrated the potential of CO2 and intermediate enrichment strategies to improve CO2 RR efficiency.

Conclusions:

• Enrichment strategies are vital for overcoming limitations in acidic CO2 RR.
• Catalyst design, electrolyte, and electrolyzer optimization are key approaches for enrichment.
• Further research into these strategies is essential for advancing carbon-neutral CO2 utilization.