Parameter Dependency of Electrochemical Reduction of CO₂ in Acetonitrile – A Data Driven Approach

The electrochemical CO₂ reduction reaction (CO₂RR) is a promising technology for the utilization of captured CO₂. Though systems using aqueous electrolytes is the state-of-the-art, CO₂RR in aprotic solvents are a promising alternative that can avoid the parallel hydrogen evolution reaction (HER). While system parameters, such as electrolyte composition, electrode material, and applied potential are known to influence the reaction mechanism, there is a lack of intuitive understanding as to how. We show that by using multivariate data analysis on a large dataset collected from the literature, namely random forest modelling, the most important system parameters can be isolated for each possible product. We find that water content, current density, and applied potential are powerful determinants in the reaction pathway, and therefore in the Faradaic efficiency of CO₂RR products.