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.