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. C-3-hydrocarbons (propene and propane) and acrolein were detected as the bulk products, whereas C-2-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 C-2-hydrocarbonated residues seem to be formed in addition to GO-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. (C) 2001 Elsevier Science B.V. All rights reserved.