Elucidation of the reaction pathways of allyl alcohol at polycrystalline palladium electrodes

The electrochemical behaviour of allyl alcohol at palladium electrodes was studied by cyclic voltammetry, chronoamperometry and on-line mass spectrometry (DEMS). The latter allows the detection of the volatile products generated during the electroreduction and electrooxidation processes. C3-hydrocarbons (propene and propane) and acrolein were detected as the bulk products, whereas C2-hydrocarbons and CO2 are related to the adsorbed species. The dissociation of the alcohol produces ethine in the 0.20–0.35 V potential range, which reduces to ethane. Adsorbed acrolein and C2-hydrocarbonated residues seem to be formed in addition to CO-like species. The results were compared with those previously obtained at platinum and gold, as well as with other unsaturated alcohols, namely benzyl and propargyl alcohol.