Modulating Spin State of Ni Single Atomic Center for High‐Performance Electrocatalytic Carbon Dioxide Reduction

Abstract Single‐atom catalysts (SACs) have been widely investigated and regarded as promising electrocatalysts for carbon dioxide reduction. However, studies on the impact of coordinated‐nitrogen species in the active center on the spin state and catalytic activity remain scarce. Herein, two single Ni atom electrocatalysts with distinct pyridinic‐N and pyrrolic‐N coordination through a rapid Joule‐heating method that preserves precursor nitrogen configurations. Magnetic susceptibility measurements reveal that pyridinic‐N induces a high‐spin state in Ni centers, while pyrrolic‐N stabilizes a low‐spin configuration. The high‐spin Ni–N pyridinic –C demonstrates an exceptional performance in electrocatalytic CO 2 reduction, achieving 98.8% CO Faradaic efficiency in H‐cells and maintaining >99% Faradaic efficiency at industrial current densities (≥250 mA cm −2 ) across alkaline, neutral, and acidic electrolytes in a gas‐diffusion flow cell. A maximum power density of 1.89 mW cm −2 and excellent charge–discharge cyclability also achieve in zinc–CO 2 battery, further demonstrating the applicability of Ni–N pyridinic –C. Theoretical calculations demonstrate that the high‐spin state enhances d‐orbital dispersion, strengthening hybridization with π* orbital of CO 2 and stabilizing *COOH intermediates, thereby accelerating CO 2 activation. This study not only establishes a novel strategy for spin‐state engineering through coordination control but also advances scalable electrocatalyst design for efficient carbon cycling.