In this work, PdFe2O3 bimetallic materials containing oxygen vacancies (O-v, from 10 to 75%) and two bimetallic nanoparticles based on noble metals (PdAu and PdPt) were obtained and evaluated for the ethanol electro-oxidation reaction (EOR) in alkaline medium. For this purpose, bimetallic nanoparticles were synthesized keeping similar crystallite sizes (similar to 6 nm), particle sizes (similar to 6 nm), mass compositions (18 +/- 4% co-metal) and metallic loadings (18.3 +/- 5.1%). PdAu/C, PdPt/C and the most active PdFe2O3/C material (75% of O-v) displayed an improved onset potential (Eons) during the oxidation of 1.5 M ethanol in 0.3 M KOH in comparison with a monometallic Pd/C material, finding the trend: PdAu/C (-0.56 V us. NHE) > PdPt/C (-0.55 V) > PdFe2O3/C (-0.51 V) > Pd/C (-0.50 V). In addition, these bimetallic materials presented an increase in the current density; being PdPt/C and PdFe2O3/C the most active materials for EOR. A spectroelectrochemical analysis was performed by coupling a mu Raman spectroscope with an electrochemical cell. This analysis allowed to conclude that the improvement of the E-onset is related to changes in chemisorption en-ergies as was suggested by Raman shifts found for the C-1-M (metal) bond, while the high activity of PdPt/C can be attributed to a higher adsorption of ethanol molecules. Addi-tionally, it was found that the activity of PdFe2O3/C is associated with an energy decrease to form the C-1-M bond, which could be promoted by the abundance of oxygen vacancies. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.