(687b) Leveraging Thermochemical Reaction Steps in the Electrocatalytic Activation of C(sp3)-H Bonds

Electrochemical synthesis pathways hold the potential to dramatically reduce the carbon footprint of the chemical industry by directly coupling increasingly decarbonized electrons into chemical reactions. These pathways contain a combination of electron transfer and purely chemical elementary steps, leading to a complex reaction network. Understanding how these individual reaction steps respond to changes in the applied potential, temperature, and other reaction conditions is necessary for the electrification of high-volume petrochemical reactions involving organic compounds. Here, we explore interplay of thermal and electrochemical reaction mechanisms in controlling the partial or total oxidation of ethanol and methane.

The partial oxidation of ethanol to form ethylene oxide is achieved using a chloride mediated pathway where kinetic control must be used to promote chlorination at the β-carbon while suppressing the thermodynamically more favorable chlorination at the α-carbon. Our experiments show that the selectivity to 2-chloroethanol is significantly impacted by the temperature and applied potential. We also use electrochemical mass spectrometry (EC-MS) to facilitate the development of methane partial oxidation catalysts. We investigated the reaction pathway that leads to the undesirable formation of CO₂ in the competitive total oxidation and found that this pathway results from the transformation of surface intermediates to *CO which must be avoided in the pursuit of methane partial oxidation.