Origin and effect of surface oxygen-containing species on electrochemical carbon/oxygen reduction reactions

Renewable-energy-powered electrochemical CO or CO2 reduction reactions (CO(2)RR) is one of the most promising strategies to upgrade CO2 to valuable products. A key question and bone of contention is whether any surface or subsurface oxygen remains on the electrocatalysts under the reducing CO(2)RR conditions, and if so, whether that oxygen play any role in facilitating the reaction.