Electrocatalytic carbon dioxide (CO2) and CO conversion is vital because it provides a pathway to efficiently valorize CO2 and incentivize CO2 capture. Furthermore, it can be done at ambient temperature and pressure. However, these reactions are typically performed under aqueous conditions which suffers from the undesired hydrogen evolution reaction (HER) from water breakdown. Aprotic nonaqueous electrolytes can suppress HER and enable a wider range of catalysts for CO2RR and CORR. Furthermore, aprotic solvents can support higher concentrations of CO2 for integrated capture and conversion (reactive capture). However, water is still needed as a proton source for hydrogenated products and to stabilize charged intermediates. Here, we study the influence of aprotic electrolyte solvent on modulating the water microenvironment, ion solvation, and dynamics for integrated CO2 capture and electrochemical conversion. Our understanding of electrolyte effects broadens the catalyst scope to earth abundant catalysts. Our work pushes the field in the understanding of electrolyte solvent and water effects for electrochemical transformations such as CO2RR, CORR and HER.
