Electrocatalytic decarboxylation of carboxylic acids over RuO2 and Pt nanoparticles

We report electrocatalytic decarboxylation (ECDX) of valeric acid into paraffins, olefins, and alcohols via (non-)Kolbe electrolysis on electrodes with RuO2 and Pt nanoparticles (NPs) as a greener alternative to thermocatalytic decarboxylation. The turnover frequency of ECDX increases, while the specific activity peaks as RuO2 NP size increases. These opposing trends make the particle size of ∼ 12 nm the optimum size for ECDX on RuO2. Bulk Pt was active for ECDX, while Pt NPs were only active for the oxygen evolution reaction under our conditions. ECDX current efficiency remained constant in the studied potential range on RuO2 NPs. Esterification was the favored reaction at 2.5 V vs. RHE; however, Kolbe electrolysis was the favored reaction at the expense of the esterification at 4.5 V vs. RHE. This work highlights the performance of nanostructured materials as an alternative to bulk materials as anodes for oxidative upgrading of carboxylic acids.