Advances and challenges of electrolyzers for large-scale CO2 electroreduction

Abstract

CO2 electroreduction (CO2ER) to high value-added chemicals is considered as a promising technology to achieve sustainable carbon neutralization. By virtue of the progressive research in recent years aiming at design and understanding of catalytic materials and electrolyte systems, the CO2ER performance (such as current density, selectivity, stability, CO2 conversion, etc.) has been continually increased. Unfortunately, there has been relatively little attention paid to the large-scale CO2 electrolyzers, which stand just as one obstacle, alongside series-parallel integration, challenging the practical application of this infant technology. In this review, the latest progress on the structures of low-temperature CO2 electrolyzers and scale-up studies was systematically overviewed. The influence of the CO2 electrolyzer configurations, such as the flow channel design, gas diffusion electrode (GDE) and ion exchange membrane (IEM), on the CO2ER performance was further discussed. The review could provide inspiration for the design of large-scale CO2 electrolyzers so as to accelerate the industrial application of CO2ER technology.