Electrochemical Oxidation Strategy for Integrated CO ₂ Capture and Conversion

The sequential CO 2 capture and conversion suffer from substantial energy penalties associated with CO 2 recovery. While direct electrochemical (bi)carbonate reduction circumvents this energy-intensive step, it still faces several limitations, including low carbon utilization efficiency, cumbersome product separation, and reliance on the anodic oxygen evolution reaction─a process hampered by slow kinetics and limited economic value. Herein, we present an electrochemical oxidation strategy that directly employs a CO 2 -captured NaOH solution─rich in (bi)carbonate ions─as the electrolyte. In this system, (bi)carbonate-mediated two-electron water oxidation reaction takes place, enabling the in situ generation of H 2 O 2 . Following electrolysis, Na 2 CO 3 ·1.5H 2 O 2, a solid crystalline adduct of Na 2 CO 3 and H 2 O 2, was readily separated from the electrolyte, thereby fixing CO 2 into a storable and value-added product. This integrated approach eliminates the need for energy-intensive CO 2 recovery, offering a streamlined route to convert captured CO 2 into easily isolable, high-value chemicals.