Reaction and reactor designs for improving electrochemical CO₂ capture

Carbon dioxide (CO₂) capture technology can help reduce atmospheric and oceanic CO₂ levels. Among existing approaches, thermochemical capture is the most widely adopted and industrially deployed method. It relies on reversible reactions between CO₂ and solid or liquid sorbents at elevated temperatures to enable separation and regeneration cycles. Compared with thermochemical systems that depend on high-temperature sorbent cycling, electrochemical CO₂ capture (ECC) offers milder operation conditions, tunable driving forces, and potentially lower energy penalties. In this review, we highlight the advantages of ECC techniques and their reaction mechanisms, energy inputs, and scalability pathways. Challenges and opportunities of ECC modifications, including chemical processes and system-level reactor designs, are highlighted from the perspectives of oxygen (O₂) sensitivity, solvent evaporation, environmental and energy costs, and scalability.