Abstract: Pd/C and Pd-Co/C electrocatalysts were prepared by sodium borohydride co-reduction and successive reduction. X-ray diffraction,?transmission electron microscopy, cyclic voltammetry, and rotating disk electrode were carried out to characterize these electrocatalysts. The results showed that the Pd-Co/C electrocatalysts have a single-phase face-centered-cubic disordered structure and the lattice constant is obviously smaller than that of Pd/C electrocatalyst. The Pd-Co/C electrocatalyst prepared by the successive reduction method not only has the highest oxygen reduction reaction activity but also shows good methanol tolerant capability.

Key words: palladium, cobalt, carbon-supported catalyst, electrocatalyst, oxygen reduction reaction, direct methanol fuel cell