Revealing the Formation and Impact of Oxygen-Containing Species on Cu Surface during CO ₂ /CO Electroreduction

High Resolution Image Download MS PowerPoint Slide Carbon dioxide/monoxide reduction reaction (CO (2) RR) on Cu catalysts presents an attractive strategy to generate valuable multicarbon hydrocarbons and oxygenates. Understanding the speciation of Cu catalysts and related surface phenomena is critical to enable the rational design of high-performance catalytic systems. In this work, we performed in situ Raman spectroscopic investigations and revealed that the previously unspecified oxygen-containing species (OCS) on Cu catalysts are most likely adsorbed hydroxyl (OH ad ) formed cathodically during CO (2) RR. Such OH ad species are further found to bind with Cu strongly, easily leading to the poisoning of Cu catalysts. We demonstrate that the pulsed CO (2) electrolysis protocol can effectively mitigate OH ad -poisoning and promote the generation of multicarbon products. Our work presents new insight into the speciation of Cu-based catalysts during the CO (2) RR and provides an important guide for the efficient production of multicarbon products in the future.