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h i g h l i g h t s g r a p h i c a l a b s t r a c t < We studied the electro-oxidation of ethylene glycol at metallic multilayer. < Metallic multilayer was composed by single and alloy compound into the intralayer. < Lower activation energy was observed for metallic multilayer. < We observed CO 2 and CO L intensity band enhancement for metallic multilayer. a b s t r a c tThis paper presents a study of the electro-oxidation of ethylene glycol (EG) at metallic multilayer electrodes: Pt pc /Ir x /Pt y (Pt pc ¼ polycrystalline Pt, x and y denote the number of monolayers of Ir intralayer and Pt outer layer, respectively) and Pt pc /(Pt 1 Ir 1 ) x /Pt y (ie a 1:1 alloy of Pt and Ir was employed as intralayer). For comparison, data are also presented for Pt pc . Although Pt and Ir have similar crystallographic structures, the work reported shows for the first time that the electrocatalytic properties of the Pt outer layer are affected significantly by the composition of the intralayer. The voltammetry data show that the Pt pc /Ir 3.0 /Pt 3.0 metallic multilayer electrode exhibits a peak current density 78% higher than that observed using Pt pc , in agreement with activation energy measurements on the electro-oxidation of EG which showed: Pt pc /Ir 3.0 /Pt 3.0 (26 kJ mol À1 ) < Pt pc (44 kJ mol À1 ) < Pt pc /(Pt 1 Ir 1 ) 3.0 /Pt 3.0 (46 kJ mol À1 ). The FTIR experiments showed that the main products for the oxidation of the diol at the electrodes are similar: CO L , CO 2 and glycolic and/or oxalic acid over Pt pc and Pt pc /Ir 3.0 /Pt 3.0 metallic multilayer electrodes. However, significantly more CO 2 and CO L were observed at Pt pc /Ir 3.0 /Pt 3.0 compared to Pt pc electrodes.