Breaking the Linear Scaling Relationship by Compositional and Structural Crafting of Ternary Cu–Au/Ag Nanoframes for Electrocatalytic Ethylene Production

Abstract

Electrocatalytic conversion of carbon dioxide into high-value multicarbon (C₂₊ ) chemical feedstocks offers a promising avenue to liberate the chemical industry from fossil-resource dependence and eventually close the anthropogenic carbon cycle but is severely impeded by the lack of high-performance catalysts. To break the linear scaling relationship of intermediate binding and minimize the kinetic barrier of CO₂ reduction reactions, ternary Cu-Au/Ag nanoframes were fabricated to decouple the functions of CO generation and C-C coupling, whereby the former is promoted by the alloyed Ag/Au substrate and the latter is facilitated by the highly strained and positively charged Cu domains. Thus, C₂ H₄ production in an H-cell and a flow cell occurred with high Faradic efficiencies of 69±5 and 77±2 %, respectively, as well as good electrocatalytic stability and material durability. In situ IR and DFT calculations unveiled two competing pathways for C₂ H₄ generation, of which direct CO dimerization is energetically favored.