Operando XRD investigation of well-defined Cu electrocatalysts at commercially viable current densities

The electrochemical CO reduction reaction (CORR) is a promising approach for the production of multicarbons products while enabling storage of renewable energy into chemical bonds. We have recently mapped the structure-reactivity relationships in copper electrocatalysts for CORR at high current densities by using well-defined Cu nanocrystals. An intriguing size and exposed facet dependence of selectivity and production rate emerged. In particular, we have found that Cu cubes and Cu octahedra produce acetate as the main product. Instead, Cu spheres uniquely promote n-propanol selectivity, which is generally obtained as a minor product in the literature. Ex-situ electron microscopy and XRD highlighted the importance of lattice strain in determining the observed reactivity. However, this analysis has some limitations. The aim of this proposal is to monitor and elucidate changes in the structure of Cu electrocatalysts during CORR by operando SAXS/WAXS X-ray total scattering.