Membrane Electrode Assembly for Electrocatalytic CO₂ Reduction: Principle and Application

Area of Science:

• Electrochemistry
• Materials Science
• Chemical Engineering

Background:

• Electrocatalytic CO2 reduction reaction (CO2 RR) in membrane electrode assembly (MEA) systems offers a promising route for CO2 utilization.
• Direct gaseous CO2 transport to cathode catalysts enhances reaction rates and system energy efficiency by eliminating liquid electrolytes.

Purpose of the Study:

• To review the principles of MEA systems for CO2 RR.
• To discuss advancements in gas diffusion electrodes, ion exchange membranes, and alternative anode processes.
• To analyze voltage distribution and identify component-specific losses.

Main Methods:

• Focus on principles of MEA design for CO2 RR.
• Examination of gas diffusion electrodes and ion exchange membranes.
• Analysis of anode processes beyond water oxidation.
• Scrutiny of voltage distribution and component losses.
• Summary of catalysts and reduced products.

Main Results:

• MEA systems enable direct gaseous CO2 delivery, boosting reaction rates.
• Absence of liquid electrolyte improves overall energy efficiency.
• Recent progress indicates potential for industrially relevant performance.
• Various reduced products and corresponding catalysts have been identified.

Conclusions:

• MEA-based CO2 RR is a viable technology with significant recent advancements.
• Understanding component-level losses is crucial for further optimization.
• Future research should address challenges and explore new opportunities for industrial application.