Design of reaction-driven active configuration for enhanced CO2 electroreduction

Metal-nitrogen-carbon single-atom catalysts (SACs) have emerged as promising candidates for electrocatalytic CO 2 reduction reaction. However, the perpendicular d z 2 orbital within planar metal site mainly interacts with *COOH, resulting in inferior CO 2 activation. Inspired by reaction-driven active configuration, here we propose to upshift nickel single-atom away from nitrogen-carbon substrate, prominently promoting the interaction between CO 2 and other d orbitals besides d z 2 . Theoretical and experimental analyses reveal that upshifting nickel site away substrate induces d xz , d yz , and d z 2 to hybridize with CO 2 , expediting CO 2 conversion to *COOH. The planar and out-of-plane Ni-N sites are formed on carbon nanosheet (Ni 1 -N/C NS ) and curved nanoparticle (Ni 1 -N/C NP ), respectively, which is verified by X-ray absorption fine structure spectroscopy. Impressively, the Ni 1 -N/C NP presents CO Faradaic efficiency of 96.4 % at 500 mA cm −2 and energy conversion efficiency of 79.8 % in flow cell, outperforming Ni 1 -N/C NS and most SACs. This work highlights the simulation of reaction-driven active sites for efficient electrocatalysis .