Identification of catalyst optimization trends for electrocatalytic CO(2) reduction to ethylene†

In this perspective we analyze copper and copper-based electrocatalysts with high ethylene selectivities from the literature to identify global catalyst formulation trends that allow for making catalysts with improved ethylene performance for industrial application. From our analysis, we identified six trends that can aid researchers in creating novel, high selectivity electrocatalysts for the electroreduction of CO₍₂₎ to ethylene. These trends were as follows. (i) Tandem-type and (ii) supported-type catalysts perform relatively more poorly than other types of systems. Engineering the nanoenvironment through implementing nanoconfining morphologies (iii) or via the addition of polymeric additives (iv) brings about significant C₂H₄ selectivity enhancements. (v) Catalyst heterogeneity is an important driver for improving C₂H₄ selectivity. (vi) Both CO₂ and CO can serve as feedstock with little impact on maximum achievable C₂H₄ selectivity. As we identified during our study that the field lacks reproducibility of catalyst performance and independent reproduction of results, we propose several strategies on how to improve. Finally, we discuss changes that authors can implement to improve the industrial relevancy of their work.