A convenient method of ternary alloys design for CO2-to-C2H4 electroreduction†

Cu-based ternary alloys have an attractive application prospect in C₂H₄ production from CO₂ electroreduction (CO₂RR). However, the rational design and development of Cu-based ternary alloys remain a significant challenge due to the complex compositional space. Here, a universal method integrating catalyst activity, selectivity and stability was proposed to design and develop Cu-based ternary alloy catalysts with better CO₂RR performance. Theoretical screening via the proposed method showed that group 8 metals can reinforce the stability of ternary Cu-alloy electrocatalysts. PtNi@Cu showed high CO₂RR performance with a low theoretical CO₂-to-C₂H₄ overpotential of 0.74 V, and demonstrated a high faradaic efficiency of 30.9% for C₂H₄ production at −1.2 V vs. RHE. In situ characterization confirmed that the CO*–COH* coupling reaction is crucial for C₂H₄ production from CO₂ electroreduction. The ternary metal synergy was favorable for electron transfer and thus strengthened the interaction of COH* with the catalyst surface for promoting C₂H₄ production from CO₂ electroreduction. This work provides a theoretical method for the rational design and development of ternary alloy catalysts.