▎ 摘　　要

The N-modified divacancies (NDs) configurations are critical to the intrinsic activity of Fe sites in Fe-N-C catalysts towards CO2 reduction reaction (CO2RR), whereas the corresponding fundamental research is still challenging and insufficient. Herein, we report the synthesis of various atomic Fe catalysts A-Fe@NG-LixKy with adjusted porous architecture. Electrochemical measurements indicate the CO2RR activity has positively relation to the ratio of edge-ND trapped Fe(II) sites [e-ND-Fe(II)] and center-ND trapped Fe(II) sites [c-ND-Fe(II)]. Theory calculations demonstrate e-ND-Fe(II) are energetically favorable for accelerating CO2RR, since the higher electron density around the Fe sites of e-ND-Fe(II) lowers the bonding of CO on the metal sites, which is confirmed by in situ attenuated total reflection-infrared spectroscopy experiments. The optimized sample A-Fe@NG-Li1K3 exhibits ultrahigh activity for CO2RR with a small overpotential of 340 mV to achieve a CO partial current density at industrial application level (97 mA cm(-2)) with a CO Faradaic efficiency of 93%.