Iron dual-atom sites for high-efficiency CO2 electroreduction at industrial-level current density

Dual-atom catalysts (DACs) with unique interactions between neighboring sites are promising candidates in the electrocatalytic CO 2 reduction reaction (CO 2 RR). Yet, the controlled synthesis of pure DACs remains a challenge to date. Herein, we propose a facile cation–anion pair adsorption-pyrolysis approach to fabricate a nitrogen-doped carbon supported Fe DAC. Based on this strategy, Fe 2 pairs can be homogeneously incorporated into the carbon substrate. When this candidate was evaluated in the electrocatalytic CO 2 RR, it exhibited a CO faradaic efficiency ( FE CO ) of ∼97 % at an industrial current density of 200 mA cm −2 in a gas diffusion electrode (GDE)-based flow cell filled with 0.5 M KHCO 3 electrolyte, surpassing most of the reported Fe based SACs. Experiments combined with theory revealed that the Fe 2 pair with enhanced electronic localization lowered the reaction free energy for COOH* formation on Fe, thereby boosting the catalytic performance in CO 2 RR. The structure–property relationship built in this study offers atomic-level insights into the rational design of electrocatalysts for efficient CO 2 RR, and extends the application of DACs for heterogeneous electrocatalysis and beyond.