Assessment of the Degradation Mechanisms of Cu Electrodes during the CO

Mom, Rik V; Sandoval-Diaz, Luis-Ernesto; Gao, Dunfeng; Chuang, Cheng-Hao; Carbonio, Emilia A; Jones, Travis E; Arrigo, Rosa; Ivanov, Danail; Hävecker, Michael; Roldan Cuenya, Beatriz; Schlögl, Robert; Lunkenbein, Thomas; Knop-Gericke, Axel; Velasco-Vélez, Juan-Jesús

Abstract

Catalyst degradation and product selectivity changes are two of the key challenges in the electrochemical reduction of CO on copper electrodes. Yet, these aspects are often overlooked. Here, we combine X-ray spectroscopy, electron microscopy, and characterization techniques to follow the long-term evolution of the catalyst morphology, electronic structure, surface composition, activity, and product selectivity of Cu nanosized crystals during the CO reduction reaction. We found no changes in the electronic structure of the electrode under cathodic potentiostatic control over time, nor was there any build-up of contaminants. In contrast, the electrode morphology is modified by prolonged CO electroreduction, which transforms the initially faceted Cu particles into a rough/rounded structure. In conjunction with these morphological changes, the current increases and the selectivity changes from value-added hydrocarbons to less valuable side reaction products, , hydrogen and CO. Hence, our results suggest that the stabilization of a faceted Cu morphology is pivotal for ensuring optimal long-term performance in the selective reduction of CO into hydrocarbons and oxygenated products.

Citation

Mom, R. V., Sandoval-Diaz, L., Gao, D., Chuang, C., Carbonio, E. A., Jones, T. E., …Velasco-Vélez, J. (in press). Assessment of the Degradation Mechanisms of Cu Electrodes during the CO. ACS applied materials & interfaces, 15(25), https://doi.org/10.1021/acsami.2c23007

• Journal Article Type: Article
• Acceptance Date: Jun 4, 2023
• Online Publication Date: Jun 15, 2023
• Deposit Date: Jul 6, 2023
• Publicly Available Date: Jul 6, 2023
• Journal: ACS applied materials & interfaces
• Print ISSN: 1944-8244
• Publisher: American Chemical Society
• Peer Reviewed: Peer Reviewed
• Volume: 15
• Issue: 25
• DOI: https://doi.org/10.1021/acsami.2c23007
• Keywords: in situ X-ray spectroscopy, in situ EC-SEM, long-term reactions, electrocatalysis, CO2RR, copper degradation