Why Methanol Electro-Oxidation on Platinum in Water Takes Place Only in the Presence of Adsorbed OH

To optimize fuel cells performance using alcohols as it is essential to untangle the mechanism of methanol electro-oxidation on platinum in aqueous medium a model reaction. Recent studies have pointed out particular necessity adsorbed OH for this process take place 1 . The here reported results, carefully obtained under low concentrations three basal planes at different scan rates discriminate between oxidation and adsorption processes, confirm such an unforeseen preceding observation 2 It elucidated that only when already present surface, CO from formed. This clear indication involved beyond providing oxygen group required oxidize CO, which has never been considered before. role played by supported DFT calculations, well reason why reaction not observed absence OH. A combination kinetic thermodynamic factors, presence multiple water molecules per molecule, high mobility favorable co-adsorption OH, virtually barrier-less hydrogen transference hydroxy yield water, result immediate activation (as soon molecule approaches surface) through substitution methoxy. In contribution will be presented change paradigm understanding how are electro-oxidized reference systems thus having crucial implications search better electrocatalysts. References: (1) Kamyabi, M. A.; Martínez-Hincapié, R.; Feliu, J. M.; Herrero, E. Effects Interfacial Structure Methanol Oxidation Platinum Single Crystal Electrodes. Surfaces 2019 https://doi.org/10.3390/surfaces2010014. (2) Mekazni, D. S.; Arán-Ais, R. Ferre-Vilaplana, Why Electro-Oxidation Water Takes Place Only Presence Adsorbed ACS Catal. 2022