Selective CO2‐to‐Syngas Conversion Enabled by Bimetallic Gold/Zinc Sites in Partially Reduced Gold/Zinc Oxide Arrays

Abstract Electrocatalytic CO 2 ‐to‐syngas (gaseous mixture of CO and H 2 ) is a promising way to curb excessive CO 2 emission and the greenhouse gas effect. Herein, we present a bimetallic AuZn@ZnO (AuZn/ZnO) catalyst with high efficiency and durability for the electrocatalytic reduction of CO 2 and H 2 O, which enables a high Faradaic efficiency of 66.4 % for CO and 26.5 % for H 2 and 3 h stability of CO 2 ‐to‐syngas at −0.9 V vs. the reversible hydrogen electrode (RHE). The CO/H 2 ratios show a wide range from 0.25 to 2.50 over a narrow potential window (−0.7 V to −1.1 V vs. RHE). In situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy combined with density functional theory calculations reveals that the bimetallic synergistic effect between Au and Zn sites lowers the activation energy barrier of CO 2 molecules and facilitates electronic transfer, further highlighting the potential to control CO/H 2 ratios for efficient syngas production using the coexisting Au sites and Zn sites.