Methanol oxidation at Pt/MoOx/MoSe2 thin film electrodes prepared with exfoliated MoSe2

This paper presents results on the dispersion of Pt on MoOx/MoSe2 electrodes, which were prepared by an intercalation–exfoliation technique. The Pt/MoOx/MoSe2 electrodes were tested for methanol oxidation by cyclic voltammetry. Thin films of MoSe2 can be oxidized electrochemically to form a MoOx layer. Compared with pure platinum, Pt/MoOx/MoSe2 electrodes gave lower oxidation potentials and higher current densities. We believe that methanol adsorption and subsequent dehydrogenation occur at the Pt atoms, while the OHads nucleation occurs at Mo sites. The presence of the adsorbed —OH groups on Mo sites may catalyze CO oxidation to CO2. This surface reaction is necessary for the improved electrocatalytic behavior of Pt/MoOx/MoSe2 electrodes.

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