Electrode Surface Heating with Organic Films Improves CO₂ Reduction Kinetics on Copper

Area of Science:

• Electrochemistry
• Chemical Engineering
• Materials Science

Background:

• Electrode surface temperature management is crucial but understudied in electrochemical reactor design.
• Complex reactions like carbon dioxide (CO2) reduction require precise control over reaction conditions.

Purpose of the Study:

• To investigate the impact of local electrode surface heating on CO2 electroreduction.
• To explore the cooptimization of mass transport and thermal effects for enhanced reaction outcomes.
• To probe the fundamental thermal effects influencing electrochemical reaction kinetics.

Main Methods:

• Utilized ferri/ferrocyanide open circuit voltage as a temperature reporter.
• Employed an organic coating on electrode surfaces for stable kinetics.
• Applied Bayesian inference and high-throughput experiments to analyze Tafel kinetic parameters.
• Investigated CO2 reduction to carbon-coupled (C2+) products on polycrystalline copper.

Main Results:

• Demonstrated that surface heating and convective cooling can be optimized for electrochemical reactions.
• Achieved well-behaved electrode kinetics with near-ambient bulk electrolyte temperatures.
• Revealed a significant decrease in overpotential (0.1 V) for C2+ products via 60°C surface heating on copper.

Conclusions:

• Local electrode surface temperature is a critical, tunable parameter for optimizing CO2 electroreduction.
• Surface heating offers a viable strategy to enhance the efficiency of producing C2+ products.
• The findings provide fundamental insights into thermal management for electrochemical processes.