Tuning Sb Atoms on Cu‐Based Catalysts for Electrochemical Conversion of CO2 to Syngas

The electrochemical CO2RR into syngas provides an attractive way to produce raw materials for synthesizing various value‐added chemicals. However, a wide range of tunable syngas ratio of CO/H2 is hard to achieve during the electrochemical CO2 conversion process. Herein, we propose a facile electrodeposition method for the preparation of Sb modified Cu‐based catalyst with a high activity for the ratio‐tunable production of syngas. The Cu10Sb1 catalyst reaches a high FE of 71% for CO at a potential of ‐1.09 V vs. RHE with the tunable CO/H2 ratio of syngas from ~0.6 to ~7.8 at the applied potentials from ‐0.78 V to ‐1.09 V. Theoretical calculations reveal the tuning effect of Sb atoms on Cu‐based catalyst for the electrochemical conversion of CO2 to syngas, in which the formation of CO on Sb modified Cu‐based catalyst possesses low energy barrier in potential‐limiting steps during CO2RR. Meanwhile, the robust charge interaction between COOH* species and the surface of Sb modified Cu‐based catalyst enhances the activity of COOH* species, thus improving FE and current for conversion into syngas products. This work brings a new strategy for the synthesis of low‐cost syngas catalyst and the tuning effect of metal atom on Cu‐based catalyst for CO2RR.