Active Sites of Au and Ag Nanoparticle Catalysts for CO2 Electroreduction to CO

Abstract Highly active and selective CO2 conversion into useful chemicals is desirable to generate valuable products out of greenhouse gases. To date, various metal-based heterogeneous catalysts have shown promising electrochemical catalytic activities for CO2 reduction, yet there have been no systematic studies of the active sites of these metal catalysts that can guide further experiments. In this study, we use first-principles calculations to identify active sites for the CO2 reduction reaction for Ag and Au metals, the two metals that have been shown to be the most active in producing CO. We compare the catalytic activity and selectivity of three reaction sites of nanoparticles, namely, low-index surfaces, edge sites, and corner sites of these metals. For nanoparticle corner sites, in particular, we find that the size effect is critical, and 309-atom (or larger) nanoparticles should …