Ampere-level electroreduction of CO₂ and CO

Electroreduction of carbon dioxide (CO₂RR) and carbon monoxide (CORR) is promising to reduce the global carbon footprint and obtain high-value products. However, both reactions are limited by the intrinsically low activity of catalysts and mass transport of reactants at the catalyst/electrolyte interface. Recent progress has highlighted the need of rational catalyst design and mass transport engineering for improving the reaction kinetics and operating the CO₂RR/CORR at current densities at ampere levels (>500 mA cm^-2). This review introduces recent advances in the CO₂RR/CORR at ampere-level current densities, especially the catalytic mechanisms and the principles for catalyst design and mass transport manipulation. The strategies for catalyst design including alloying and doping, single atom effects, regulating the morphology and structure, oxidation state control, and organic molecule functionalization are reviewed together with the mass transfer manipulation through electrode engineering and electrolyzer optimization. The challenges and perspectives are discussed for further industrial development in this field.