Anion intercalation enables efficient and stable carboxylate upgrading via aqueous non-Kolbe electrolysis

Next-generation techniques for sustainable carboxylate production generate carboxylate salts as the primary outcome. To circumvent the costly conversion of carboxylate salts to acids, we demonstrate the aqueous (non-)Kolbe electrolysis process as an alternative strategy to generate downstream value-added chemicals. Upon revealing the irreversible oxidation-induced charge transfer inhibition on the graphite anode, we propose an anion intercalation strategy to mitigate the stability problem induced by the ever-increasing overpotential. In acetate decarboxylation, we observe a high Faradaic efficiency of ~95% for non-Kolbe products (methanol and methyl acetate) at wide current densities ranging from 0.05 to 1 A cm−2 and long-term stability at current densities of 0.15 and 0.6 A cm−2 for 130 and 35 h, respectively. We also extended this strategy for the upgrading of long-chain carboxylates such as propionate, butyrate, and succinate. Our work provides valuable guidance for carboxylate upgrading and extendable strategy for overcoming passivation challenges in catalysis. Here, the authors propose an anion intercalation strategy to mitigate the stability problem of aqueous non-Kolbe electrolysis, which enables the efficient upgrading of carboxylate salts to value-added chemicals.