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Updated: Nov 14, 2025

Synthesis and Performance Characterizations of Transition Metal Single Atom Catalyst for Electrochemical CO2 Reduction
Published on: April 10, 2018
Cu(I) Reducibility Controls Ethylene vs Ethanol Selectivity on (100)-Textured Copper during Pulsed CO2 Reduction
Zhichu Tang1, Emily Nishiwaki1,2, Kevin E Fritz1
1Department of Materials Science and Engineering, Cornell University, Ithaca, New York 14853, United States.
Abstract:
The electrochemical CO2 reduction reaction (CO2RR) can convert widely available CO2 into value-added C2 products, such as ethylene and ethanol. However, low selectivity toward either compound limits the effectiveness of current CO2RR electrocatalysts. Here, we report the use of pulsed overpotentials to improve the ethylene selectivity to 67% with >75% overall C2 selectivity on (100)-textured polycrystalline Cu foil. The pulsed CO2RR can be made selective to either ethylene or ethanol by controlling the reaction temperature. We attribute the enhanced C2 selectivity to the improved CO dimerization kinetics on the active Cu surface on predominately (100)-textured Cu grains with the reduced hydrogen adsorption coverage during the pulsed CO2RR. The ethylene vs ethanol selectivity can be explained by the reducibility of the Cu(I) species during the cathodic potential cycle. Our work demonstrates a simple route to improve the ethylene vs ethanol selectivity and identifies Cu(I) as the species responsible for ethanol production.
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