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DOE OSTI · 1826553

Dynamic Boundary Layer Simulation of Pulsed CO 2 Electrolysis on a Copper Catalyst

Bui, Justin C.·Kim, Chanyeon·Weber, Adam Z.·Bell, Alexis T.
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Abstract

Pulsed electrolysis has been demonstrated to improve the faradaic efficiency (FE) to C 2+ products during the electrochemical reduction of CO 2 over a Cu catalyst, but the nature of this enhancement is poorly understood. Herein, we developed a time-dependent continuum model of pulsed CO 2 electrolysis on Cu in 0.1 M CsHCO 3 that faithfully represents the experimentally observed effects of pulsed electrolysis. This work shows that pulsing results in dynamic changes in the pH and CO 2 concentration near the Cu surface, which lead to an enhanced C 2+ FE as a consequence of repeatedly accessing a transient state of heightened pH and CO 2 concentration at high cathodic overpotential. Using these insights, a variety of pulse shapes were explored to establish operating conditions that maximize the rate of C 2+ product formation and minimize the rates of H 2 and C 1 product formation.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRYElectrical propertiesElectrodesElectrolysisElectrolytesThickness

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Bui, Justin C., Kim, Chanyeon, Weber, Adam Z., Bell, Alexis T.. 2021-03-11. Dynamic Boundary Layer Simulation of Pulsed CO 2 Electrolysis on a Copper Catalyst. https://doi.org/10.1021/acsenergylett.1c00364

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