Electrochemical Conversion of CO₂ to Syngas with Controllable CO/H₂ Ratios over Co and Ni Single‐Atom Catalysts

Abstract

Abstract The electrochemical CO 2 reduction reaction (CO 2 RR) to yield synthesis gas (syngas, CO and H 2 ) has been considered as a promising method to realize the net reduction in CO 2 emission. However, it is challenging to balance the CO 2 RR activity and the CO/H 2 ratio. To address this issue, nitrogen‐doped carbon supported single‐atom catalysts are designed as electrocatalysts to produce syngas from CO 2 RR. While Co and Ni single‐atom catalysts are selective in producing H 2 and CO, respectively, electrocatalysts containing both Co and Ni show a high syngas evolution (total current >74 mA cm −2 ) with CO/H 2 ratios (0.23–2.26) that are suitable for typical downstream thermochemical reactions. Density functional theory calculations provide insights into the key intermediates on Co and Ni single‐atom configurations for the H 2 and CO evolution. The results present a useful case on how non‐precious transition metal species can maintain high CO 2 RR activity with tunable CO/H 2 ratios.