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Abstract With rising CO2emissions and growing interests towards CO2valorization, electrochemical CO2reduction (eCO2R) has emerged as a promising prospect for carbon recycling and chemical energy storage. Yet, product selectivity and electrocatalyst longevity persist as obstacles to the broad implementation of eCO2R. A possible solution to ameliorate this challenge is to pulse the applied potential. However, it is currently unclear whether and how the trends and lessons obtained from the more conventional constant potential eCO2R translate to pulsed potential eCO2R. In this work, we report that the relationship between electrolyte concentration/composition and product distribution for pulsed potential eCO2R is different from constant potential eCO2R. In the case of constant potential eCO2R, increasing KHCO3concentration favors the formation of H2and CH4. In contrast, for pulsed potential eCO2R, H2formation is suppressed due to the periodic desorption of surface protons, while CH4is still favored. In the case of KCl, increasing the concentration during constant potential eCO2R does not affect product distribution, mainly producing H2and CO. However, increasing KCl concentration during pulsed potential eCO2R persistently suppresses H2formation and greatly favors C2products, reaching 71 % Faradaic efficiency. Collectively, these results provide new mechanistic insights into the pulsed eCO2R mechanism within the context of proton‐donator ability and ionic conductivity.
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This content will become publicly available on June 10, 2026
Plastic from CO 2 , Water, and Electricity: Tandem Electrochemical CO 2 Reduction and Thermochemical Ethylene‐CO Copolymerization
Abstract Converting CO2into industrially useful products is an appealing strategy for utilization of an abundant chemical resource. Electrochemical CO2reduction (eCO2R) offers a pathway to convert CO2into CO and ethylene, using renewable electricity. These products can be efficiently copolymerized by organometallic catalysts to generate polyketones. However, the conditions for these reactions are very different, presenting the challenge of coupling microenvironments typically encountered for the transformation of CO2into highly complex but desirable multicarbon products. Herein, we present a system to produce polyketone plastics entirely derived from CO2and water, where both the CO and C2H4intermediates are produced by eCO2R. In this system, a combination of Cu and Ag gas diffusion electrodes is used to generate a gas mixture with nearly equal concentrations of CO and C2H4, and a recirculatory CO2reduction loop is used to reach concentrations of above 11% each, leading to a current‐to‐polymer efficiency of up to 51% and CO2utilization of 14%.
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- Award ID(s):
- 2400314
- PAR ID:
- 10632989
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Angewandte Chemie International Edition
- Volume:
- 64
- Issue:
- 24
- ISSN:
- 1433-7851
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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