Electrocatalytic CO₂ Reduction to C₂₊ Products in Flow Cells

Electrocatalytic CO 2 reduction into value‐added fuels and chemicals by renewable electric energy is one of the important strategies to address global energy shortage and carbon emission. Though the classical H‐type electrolytic cell can quickly screen high‐efficiency catalysts, the low current density and limited CO 2 mass transfer process essentially impede its industrial applications. The electrolytic cells based on electrolyte flow system (flow cells) have shown great potential for industrial devices, due to higher current density, improved local CO 2 concentration, and better mass transfer efficiency. The design and optimization of flow cells are of great significance to further accelerate the industrialization of electrocatalytic CO 2 reduction reaction (CO 2 RR). In this review, the progress of flow cells for CO 2 RR to C 2+ products is concerned. Firstly, the main events in the development of the flow cells for CO 2 RR are outlined. Second, the main design principles of CO 2 RR to C 2+ products, the architectures, and types of flow cells are summarized. Third, the main strategies for optimizing flow cells to generate C 2+ products are reviewed in detail, including cathode, anode, ion exchange membrane, and electrolyte. Finally, the preliminary attempts, challenges, and the research prospects of flow cells for industrial CO 2 RR toward C 2+ products are discussed.