The electrochemical upgrading of bio‐oil offers a promising pathway to produce high‐value bioproducts; however, the reaction pathways are still not well understood. This study investigates, for the first time, the effects of introducing an oxidative pulse on the product distribution during the electrocatalytic reduction of glucose, a key bio‐oil model compound. At a constant current density of −10 mA/cm2 on Pb, glucose was primarily reduced to sorbitol (53% selectivity) and 2‐deoxysorbitol (14% selectivity), via hydrogenation and deoxygenation pathways. Isomerization of glucose to fructose was also observed. When oxidative pulses were introduced, significant changes in product distribution occurred. While the sorbitol selectivity remained unchanged, the selectivity for 2‐deoxysorbitol increased with increasing pulse frequency. Although not proven, this could suggest that transient surface oxidation, for example, by the formation of a PbO layer, favors deoxygenation. These findings reveal a new function and benefits of oxidative pulses in modulating product distribution, offering insights for tuning product selectivity and yields during electrochemical upgrading of bio‐oil.
Gouws et al. (Sun,) studied this question.