The Role of Atomic Carbon in Directing Electrochemical CO(2) Reduction to Multicarbon Products

Electrochemical reduction of carbon-dioxide/carbon-monoxide (CO₍₂₎R) to fuels and chemicals presents an attractive approach for sustainable chemical synthesis, but also poses a serious challenge in catalysis. Understanding the key aspects that guide CO₍₂₎R towards value-added multicarbon (C₂₊) products is imperative in designing an efficient catalyst. Herein, we identify the critical steps toward C₂ products on copper through a combination of energetics from density functional theory and micro-kinetic modeling. We elucidate the importance of atomic carbon in directing C₂₊ selectivity and how it introduces surface structural sensitivity on copper catalysts. This insight enables us to propose two simple thermodynamic descriptors that effectively describe C₂₊ selectivity on metal catalysts beyond copper and hence it identifies an intelligible protocol to screen for materials that selectively catalyze CO₍₂₎ to C₂₊ products.