The electrochemical reduction of carbon dioxide (CO2R) driven by renewably generated electricity (e.g., solar and wind) offers a promising means for reusing the CO2 released during the production of cement, steel, and aluminum, as well as the production of ammonia and methanol. Cu is the best suited single metal electrocatalyst, since it is able to produce hydrocarbons and oxygenated compounds with much higher faradaic efficiency than can be achieved with alternative catalysts. In this presentation, we will examine the effects of catalyst morphology on the production of multicarbon (C2+) products and then explore the role of mass transfer combined with the kinetics of buffer reactions on the local concentration of CO2 and pH at the catalyst surface. This is followed by a discussion of the dependence of local CO2 concentration and pH on the dynamics of CO2R and the formation of specific products is discussed. Next, we summarize the impact of electrolyte cation identity on the rate of CO2R and the distribution of products. Subsequently, we look at utilizing pulsed electrolysis to tune the local pH and CO2 concentration at the catalyst surface. In the last part of the presentation we show that ionomer-coated catalysts in combination with pulsed electrolysis can enable attainment of very high (&gt; 90 %) selectivity to C2+ products over Cu in aqueous electrolyte with minimum co-generation of H2.

Fundamental processes influencing the electrochemical reduction of CO2 on Cu

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.