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