(646i) Solvation Effects for Nonaqueous CO2 Electrochemistry

Carbon dioxide (CO2) conversion is vital because it provides a pathway to efficiently valorize CO2 and incentivize CO2 capture. Electrocatalytic CO2 conversion is of great interest because it is scalable and can be done at ambient temperature and pressure. However, these reactions are typically performed in water which suffers from undesired hydrogen evolution reaction (HER) from water breakdown. Aprotic nonaqueous electrolytes can suppress HER and enable a wider range of catalysts for CO2RR. However, water is still needed as a proton source and to stabilize charged intermediates. Here, we study the influence of aprotic electrolyte solvent on modulating the water microenvironment, solvation, and dynamics. Furthermore, we probe changes to the water chemical environment in different aprotic media and the ability of aprotic electrolytes to enhance CO2RR or suppress HER. Our work pushes the field in the understanding of electrolyte solvent and water effects for electrochemical transformations such as CO2RR and HER.