TY - JOUR A1 - Mangoufis-Giasin, I. A1 - Piqué, O. A1 - Khanipour, Peyman A1 - Mayrhofer, K. J. J. A1 - Calle-Vallejo, F. A1 - Katsounaros, I. T1 - Different promoting roles of ruthenium for the oxidation of primary and secondary alcohols on PtRu electrocatalysts JF - Journal of catalysis N2 - This study shows remarkably different features between the oxidation of secondary and primary C₃-C₅ alcohols. The oxidation of primary alcohols is controlled by the oxidative removal of blocking adsorbates, such as CO, formed after the dissociative adsorption of alcohol molecules. Conversely, secondary alcohols do not undergo dissociative adsorption and therefore their oxidation is purely controlled by the energetics of the elementary reaction steps. In this respect, a different role of ruthenium is revealed for the electrooxidation of primary and secondary alcohols on bimetallic platinum-ruthenium catalysts. Ruthenium enhances the oxidation of primary alcohols via the established bifunctional mechanism, in which the adsorption of (hydr)oxide species that are necessary to remove the blocking adsorbates is favored. In contrast, the oxidation of secondary alcohols is enhanced by the Ru-assisted stabilization of an O-bound intermediate that is involved in the potential-limiting step. This alternative pathway enables the oxidation of secondary alcohols close to the equilibrium potential. KW - Electrocatalysis KW - Electrochemical energy conversion KW - Direct alcohol fuel cells KW - Alcohol electrooxidation KW - Secondary alcohols KW - 2-propanol oxidation KW - Electrochemical real-time mass spectrometry KW - Density functional theory PY - 2021 DO - https://doi.org/10.1016/j.jcat.2021.05.028 SN - 0021-9517 VL - 400 SP - 166 EP - 172 PB - Elsevier CY - San Diego, Calif. AN - OPUS4-56999 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -