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

Abstract The electrochemical CO 2 RR 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/H 2 is hard to achieve during the electrochemical CO 2 conversion process. Herein, we propose a facile electrodeposition method for the preparation of Sb modified Cu‐based catalysts with a high activity for the ratio‐tunable production of syngas. The Cu 10 Sb 1 catalyst reaches a high FE of 71% for CO at a potential of −1.09 V versus RHE with the tunable CO/H 2 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 CO 2 to syngas, in which the formation of CO on Sb modified Cu‐based catalyst possesses lower energy barrier in potential‐limiting steps during CO 2 RR. 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 density 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 CO 2 RR.