Pd nanoparticles on Co nanofilms as composite electrocatalysts for ethanol oxidation in alkaline solution

Carbon-supported composite electrocatalysts of Pd nanoparticles implanted on Co nanofilms (Pdx/Co-nanofilm/C) were synthesized on an immiscible ionic liquid/water interface by a sequential reduction approach. Controllable metal nanostructures (Pd nanoparticles, Co nanofilms) and highly dispersed Pdx/Co-nanofilms on carbon are achieved through simple strategies. The Pd nanoparticles implanted on Co nanofilms evidently exhibit crystal lattice distortion and surface roughness. Thus prepared Pd3/Co-nanofilm/C catalyst demonstrates the highest activity toward ethanol oxidation reaction (EOR), with the lowest onset potential shifting negatively about 100 mV, the most negative peak potential, and the highest peak current compared with those of Pd3Co/C and pure Pd/C catalysts in alkaline solution. Chronoamperometric results also demonstrate higher current values produced by the Pd3/Co-nanofilm/C catalyst. We proposed that the EOR activity enhancement of Pdx/Co-nanofilm/C catalysts may be attributed to a modulation of the structural properties of Pd nanoparticles through the 2D Co-nanofilm substrate, as well as a synergistic effect between Pd nanoparticles and the Co-nanofilm substrate.