Synergistic Ag/Cu dual-site catalysis enables high-efficiency CO₂ electroreduction to C₂₊ products

The electrochemical conversion of CO₂ to C₂₊ products represents a significant technological opportunity for addressing global climate change. Nevertheless, copper-based catalysts continue to present challenges in terms of selectivity and the long-term stability of C₂₊ products. In this study, we demonstrate that the introduction of a second metal, silver (Ag), onto copper-based catalysts represents an effective strategy for enhancing the selectivity and reactivity of these catalysts in the electrochemical CO₂ reduction reaction. This approach involves modulating the adsorption strength or geometry of CO intermediates on the Cu-based catalyst surface. The results demonstrate that the Faradaic efficiency (FE) of C₂₊ products in the electrochemical CO₂ reduction reaction over a 5% Ag/Cu catalyst is 77%–80% within the current density range of 800 to 1000 mA·cm⁻². Furthermore, stability tests were conducted on the electrochemical CO₂ reduction reaction in a membrane electrolyzer using pure water as the electrolyte. Following a 15 h testing period at a current of −1000 mA, the FE of CO₂ reduction was observed to be 45%, indicating favorable stability. This provides a foundation for further research and development in the industrial application of electrochemical CO₂ reduction.