Resumen: In this work, palladium-nickel nanoparticles supported on carbon nanofibers were synthesized, with metal contents close to 25 wt % and Pd:Ni atomic ratios near to 1:2. These catalysts were previously studied in order to determine their activity toward the oxygen reduction reaction. Before the deposition of metals, the carbon nanofibers were chemically treated in order to generateoxygen and nitrogen groups on their surface. Transmission electron microscopy analysis (TEM) images revealed particle diameters between 3 and 4 nm, overcoming the sizes observed for thenanoparticles supported on carbon black (catalyst Pd-Ni CB 1:2). From the CO oxidation at different temperatures, the activation energy Eact for this reaction was determined. These values indicated a high tolerance of the catalysts toward the CO poisoning, especially in the case of the catalystssupported on the non-chemically treated carbon nanofibers. On the other hand, apparent activation energy Eap for the methanol oxidation was also determined finding—as a rate determining step—the COads diffusion to the OHads for the catalysts supported on carbon nanofibers. The results here presented showed that the surface functional groups only play a role in the obtaining of lower particlesizes, which is an important factor in the obtaining of low CO oxidation activation energies. Idioma: Inglés DOI: 10.3390/nano6100187 Año: 2016 Publicado en: Nanomaterials 6, 10 (2016), 6100187 [18 pp.] ISSN: 2079-4991 Factor impacto JCR: 3.553 (2016) Categ. JCR: MATERIALS SCIENCE, MULTIDISCIPLINARY rank: 58 / 275 = 0.211 (2016) - Q1 - T1 Categ. JCR: NANOSCIENCE & NANOTECHNOLOGY rank: 33 / 87 = 0.379 (2016) - Q2 - T2 Factor impacto SCIMAGO: 0.0 - Materials Science (miscellaneous) - Chemical Engineering (miscellaneous)