Silver modified copper foam electrodes for enhanced reduction of CO to C products

Electrochemical CO 2 reduction reactions (CO 2 RRs) have been recognized as a promising solution to environmental and energy problems due to their ability to convert intermittent renewable electricity into hydrocarbon fuels and value-added chemicals. Copper has a unique ability to electrochemically reduce CO 2 to produce C 2+ hydrocarbon products compared to other metals. However, it is still suffering from low Faraday efficiency (FE) limitations for specific products. Herein, we have prepared an Ag-modified Cu/CuO-Ag catalyst with a porous structure via a galvanic replacement reaction method, which reduced CO 2 to C 2+ products with the FE of 52.5% at −1.1 V ( vs. RHE). The experimental results and density functional theory (DFT) calculations show that the addition of Ag in Cu is beneficial to increasing the coverage of *CO on the Cu surface, which can decrease the potential barrier energy of the C-C coupling reaction and favor the generation of C 2+ products. The results of this study may be helpful to the design of efficient tandem catalysts for electrochemical CO 2 reduction. Here we report an Ag-modified Cu/CuO (Cu/CuO-Ag) catalyst with a porous 3D structure, which can efficiently electrochemically reduce CO 2 to ethylene and other C 2+ products.