Steps Control the Dissociation of CO₂ on Cu(100)

Abstract

CO₂ reduction reactions, which provide one route to limit the emission of this greenhouse gas, are commonly performed over Cu-based catalysts. Here, we use ambient pressure X-ray photoelectron spectroscopy together with density functional theory to obtain an atomistic understanding of the dissociative adsorption of CO₂ on Cu(100). We find that the process is dominated by the presence of steps, which promote both a lowering of the dissociation barrier and an efficient separation between adsorbed O and CO, reducing the probability for recombination. The identification of steps as sites for efficient CO₂ dissociation provides an understanding that can be used in the design of future CO₂ reduction catalysts.