Asymmetric Coordination Induced Electron Localization of Fe–Mn Alloy for CO 2 Electroreduction

Electrocatalysts of transition metal alloys have attracted enormous attention for carbon dioxide reduction reaction, but they still suffer from the low current density to meet the industrial requirement, mainly attributed to the difficulties in activating CO 2 to generate COOH* intermediate. Herein, we introduce an asymmetric coordination for Fe–Mn alloy supported on N-doped carbon nanosheets (Fe 0.75 Mn 0.25 @NC) synthesized through a multistep approach involving hard template and secondary pyrolysis. The Fe 0.75 Mn 0.25 @NC electrocatalyst achieves an impressive CO faradaic efficiency of 97.6% at −0.6 V versus the reversible hydrogen electrode (RHE). When assembled in a gas diffusion electrode, Fe 0.75 Mn 0.25 @NC exhibits an exceptionally high CO partial current density of 505 mA/cm 2 in the flow cell. Theoretical calculations highlight that incorporating Mn gives rise to an asymmetric coordination in Fe 0.75 Mn 0.25 @NC, enhancing the electronic localization of Fe, which facilitate the CO 2 activation capability to form COOH* intermediate, thus improving both the selectivity and activity toward CO production.