High-Performance Electrocatalytic CO2 Reduction for CO Generation Using Hydrophobic Porous Carbon Supported Au

Electrocatalytically reducing gaseous CO2 to high value-added chemical fuels is an ideal method to address energy and environmental issues. To achieve high Faradic efficiency (FE) of specific products with high current density for the CO2 reduction reaction (CO2RR), it is crucial to design suitable electrocatalysts to understand the relationship of structure and performance. Herein, we synthesized a hydrophobic porous carbon scaffold loaded with Au nanoparticles to explore the effect of the porous structure on CO2RR performance. As high as 92% FE of CO is achieved over the optimized 20%Au/FPC-800 electrocatalyst within the applied potential range of −0.7 to −1.1 V versus RHE, and its current density toward CO2RR is also much larger than that of other three electrocatalysts for comparison. Based on the characterization of CO2 adsorption/desorption, Tafel slope, electrochemical impedance spectroscopy (EIS), and in situ attenuated total reflection-surface-enhanced infrared absorption spectroscopy (ATR-SEIRAS) analysis, it is proposed that the hydrophobic porous structure favors CO2 storage, which can enhance the mass transfer of low-soluble CO2 molecules to the electrocatalyst interface during CO2RR. Our findings provide a strategy for achieving high FE of converting CO2 to generate a CO product with a high current density.