(343f) Understanding the Influence of [EMIM] Cl on the Suppression of the Hydrogen Evolution Reaction on Transition Metal Electrodes

Feaster, J. T., Stanford University
Jongerius, A. L., Stanford University
Nitopi, S., Stanford University
Hahn, C., Stanford University
Chan, K., SUNCAT Center for Interface Science and Catalysis, Stanford University and SLAC National Accelerator Laboratory
Urushihara, M., SUNCAT Center for Catalysis and Interface Science
Nørskov, J. K., Stanford University and SLAC National Laboratory
Jaramillo, T. F., Stanford University
Ionic liquids have recently been suggested to suppress the hydrogen evolution reaction (HER), as well as increase selectivity and activity for CO2 reduction to high value chemicals and fuels. To learn more about the origin of this effect, we have studied the influence of the ionic liquid 1-ethyl-3-methylimidazolium chloride ([EMIM] Cl) on HER on Ag, Cu and Fe electrodes in acidic and basic media. In the absence of CO2, HER is suppressed on all three electrodes in acidic media; no such suppression is observed in basic media. Furthermore, we used 1H NMR spectroscopy to identify compounds that are formed as the [EMIM] Cl breaks down at both the working and counter electrodes under electrochemical reaction conditions.