Integrated Electrochemical CO₂ Capture with Energy Storage for Renewable Energy Compatibility

Carbon capture via electrochemical processes can benefit from direct integration with renewable power plants, but the intermittency of renewable energy sources makes efficient operation challenging. Here, we demonstrate an integrated electrochemical carbon capture and energy storage system that enhances adaptability to intermittent renewable energy sources. By splitting the single CO₂/sorbent regeneration step into two separate electrolyzers via insertion of the ferrocyanide/ferricyanide redox pair, we successfully demonstrated energy storage during the alkaline sorbent regeneration, while providing energy output during the CO₂ regeneration step. Our decoupled electrolyzer system achieved a net energy consumption of 68.9-248.7 kJ/mol for overall carbon capture at 10-100 mA/cm², and delivered an energy output of 54 kJ/mol-CO₂ at 10 mA/cm² during the CO₂ regeneration step, demonstrating its potential compatibility with intermittent energy sources.