Comparative analysis of electrolyzers for electrochemical carbon dioxide conversion

Electrochemical carbon dioxide (CO2) conversion to fuels and chemicals provides a long-term and large-scale storage solution for intermittent renewable electricity. In the last few decades, most of the effort has been devoted to developing new catalysts to improve CO2 reduction performance. Very recently, advances in system design, including electrochemical cell design and electrochemical operating conditions, have led to a significant improvement in CO2 conversion efficiency. In this review, we describe system design strategies in the context of boosting key performance metrics in CO2 conversion: current density, Faradaic efficiency, energy efficiency, stability, reactant utilization and product concentration, carbonate formation and CO2 crossover. The advantages and limitations of each strategy, in terms of overall CO2 conversion performance, are discussed. This review offers guidelines for developing a high-performance electrochemical CO2 conversion system to bring this technology closer to practical implementation.