Document Type
Article
Publication Date
3-31-2024
Abstract
Ethylene is well known as the primary product of CO2 reduction at Cu electrocatalysts using zero-gap membrane electrode assembly cells with gas diffusion cathodes. Other types of Cu electrocatalysts including oxide-derived Cu, CuSn and CuSe yield relatively more C2 oxygenates; however, the mechanisms for C2 product selectivity are not well established. This work considers selectivity trends of Cu-P0.065, Cu-Sn0.03, and Cu2Se electrocatalysts made using a standard one pot synthesis method. Results show that Cu-P0.065 electrocatalysts (Cuδ+ = 0.13) retain ethylene as a primary product with relatively higher Faradaic efficiencies (FE = 43% at 350 mA cm−2) than undoped Cu electrocatalysts (FE = 31% at 350 mA cm−2) at the same current density. The primary CO2 reduction product at Cu-Sn0.03 (Cuδ+ = 0.27) electrocatalysts shifts to ethanol (FE = 48% at 350 mA cm−2) while CO2 reduction at Cu2Se (Cuδ+ = 0.47) electrocatalysts favor acetate production (FE = 40% at 350 mA cm−2). Based on these results, we propose a common acetyl intermediate and a mechanism for selective formation of ethylene, ethanol or acetate based on the degree of partial positive charge (δ + ) of Cu reaction sites.
Publication Source (Journal or Book title)
Journal of the Electrochemical Society
Recommended Citation
Dauda, M., Hendershot, J., Bello, M., Park, J., Loaiza Orduz, A., Lombardo, N., Kizilkaya, O., Sprunger, P., Engler, A., Plaisance, C., & Flake, J. (2024). Electrochemical Reduction of CO2: A Common Acetyl Path to Ethylene, Ethanol or Acetate. Journal of the Electrochemical Society, 171 (3) https://doi.org/10.1149/1945-7111/ad2cc1