Constructing FeN4/graphitic nitrogen atomic interface for high-efficiency electrochemical CO2 reduction over a broad potential window

•Eliminating H2 generation catalytic sites with H2-etching-pyrolysis•Constructed an “atomic interface” between single metal atom non-metal atom•Observed the CO2 and H2O both participate in CO2RR through situ ATR-SEIRAS•High selectivity a FECO above 90% over very broad potential range The development of low-cost, high-performance electrocatalysts for electrochemical reduction reaction (CO2RR) investigation related mechanism are crucial importance to solve problems greenhouse effect energy shortage, yet such tasks remain rather challenging. In this work, we developed selective etching strategy remove undesired H2-producing Fe–N–C put forward new concept metal/non-metal as robust catalyst promoting activation protonation assistance co-adsorbed H2O, which greatly broadens featuring high CO2-to-CO selectivity. This work not only demonstrates rational design precise structural modulation nitrogen-doped single-atom catalysts but also enables us tandem subsequent synthesis high-valued hydrocarbons. Atomically dispersed has shown great performance conversion, CO is achieved within narrow range, cannot well meet requirements following dimerization or hydrogenation. Here, hydrogen-pyrolysis precisely manipulate uncoordinated N dopants catalyst. could preferentially eliminate pyridinic pyrrolic atoms while leaving graphitic N. resulting gave faradaic efficiency (FECO) window from ?0.3 ?0.8 V (versus RHE) (in particular, > 97% at ?0.6 V). ATR-SEIRAS first-principle calculations further revealed that can suppress parasitic promote on “FeN4/graphitic N.” overdependence petrochemical resulted excessive amount emitted gas atmosphere. Electrochemical hydrocarbon fuels attractive overcome some environment sectors.1Hori Y. electrodes.in: Modern Aspects Electrochemistry. Vol 42. 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