Ionomer-Driven Reaction Microenvironment Control in Bicarbonate-Mediated Integrated CO₂ Capture and Electrolysis.

Area of Science:

• Electrochemistry
• Materials Science
• Chemical Engineering

Background:

• Bicarbonate electrolysis offers an energy-efficient route for CO2 capture and electrochemical conversion.
• Current limitations include low reaction rates and energy efficiency, hindering practical application.

Purpose of the Study:

• To enhance bicarbonate electrolysis performance by manipulating reaction microenvironments.
• To improve the efficiency of CO2 capture and electrochemical conversion processes.

Main Methods:

• Incorporation of ionomers, specifically Nafion, into cobalt phthalocyanine (CoPc) electrodes.
• Characterization of electrode structure and finite element simulation.
• Testing in a cation exchange membrane-based zero-gap electrolyzer with simulated flue gas.

Main Results:

• Nafion-incorporated CoPc electrodes achieved a maximum CO partial current density of 410 mA cm⁻² at 3.09 V.
• Enhanced proton conductivity increased local CO2 concentration around the catalyst.
• Demonstrated a closed-loop system for integrated CO2 capture and electrolysis.

Conclusions:

• Manipulating reaction microenvironments with ionomers significantly improves bicarbonate electrolysis.
• The developed electrode material shows great promise for efficient, integrated CO2 capture and conversion.
• This approach advances sustainable carbon capture and utilization technologies.