The Bidentate Adsorption Mode of Re-Ni Atomic Pairs Inducing the Ultralow Overpotential in CO2 Electroreduction.

Developing highly efficient, selective, and low-overpotential electrocatalysts for the electrochemical carbon dioxide reduction reaction (eCO2R) is crucial for mitigating atmospheric CO2 levels and enabling carbon-neutral energy cycles. Herein, inspired by the activation mechanism of natural carbon monoxide dehydrogenase, we fabricated a Re-Ni dual-atom catalyst supported on a nitrogen-doped carbon catalyst (ReNi-N/C), featuring adjacent Re-Ni atomic pairs, that exhibits outstanding eCO2R performance with a CO partial current density of -427.6 mA cm-2 and near 100% Faradaic efficiency for CO (FECO). Notably, it operates at an ultralow overpotential of 0.16 V to achieve a CO partial current density of -27.0 mA cm-1 and maintains over 95% FECO within a broad potential range from -0.27 V to -0.80 V. In situ spectroscopy and density functional theory (DFT) calculations reveal that the formation of Re-Ni pairs not only induces a downshift by 0.22 eV of the Ni d-band center but also enables a bidentate adsorption configuration of the *COOH intermediate on the Ni-Re site, which accelerates *COOH formation and *CO desorption, thereby achieving high activity and selectivity in eCO2R. This work demonstrates a new strategy and theoretical basis for the rational design of bimetallic sites toward efficient CO2 reduction electrocatalysts.