The development of convenient and highly efficient synthetic route to fabricate single-atom catalysts anchored on N-doped carbon nanosheets remains a big challenge for CO₂ electrochemical reduction (CO₂RR). Herein, we develop a one-step molten-salt-assisted synthesis combined with temperature-programmed thermal activation method to fabricate Fe single-atom supported on N-doped carbon nanosheets (FeNC NSs) for CO₂RR. In a flow cell, CO partial current density of FeNC NSs-1000 up to 147.9 mA cm^-2 at − 0.66 V with a high turnover frequency above 1 × 10⁵ h^-1 is achieved. Experimental results reveal that the active site was the center Fe atom coordinated with four N atoms, accelerating the formation of *COOH intermediate and thus accounts for its superior CO₂-CO conversion activity. Theoretical calculations further manifest that the pyrrolic N in second coordination sphere reduces the energy barrier of rate-limiting step and promotes the electron transfer capacity. Moreover, the FeNC NSs-1000 is applied as cathode to rechargeable Zn-CO₂ battery, exhibiting high CO selectivity and superior stability.

开发便捷高效的合成路线来制造锚定在 N 掺杂碳纳米片上的单原子催化剂仍然是 CO ₂电化学还原 (CO ₂ RR) 的一大挑战。在此，我们开发了一种一步熔盐辅助合成结合程序升温热活化方法来制造 CO 2 RR 负载在 N 掺杂碳纳米片 (FeNC NSs) 上的 Fe 单_原子。在流通池中，FeNC NSs-1000 的 CO 部分电流密度在 − 0.66 V 时高达 147.9 mA cm ^-2且转换频率高于 1 × 10 ⁵ h ^-1已完成。实验结果表明，活性位点是与四个N原子配位的中心Fe原子，加速了*COOH中间体的形成，从而解释了其优异的CO 2 _-CO转化活性。理论计算进一步表明，第二配位层中的吡咯N降低了限速步骤的能垒，提高了电子转移能力。此外，FeNC NSs-1000 用作可充电 Zn-CO ₂电池的正极，表现出高 CO 选择性和优异的稳定性。