PdCu alloy nanoparticles supported on reduced graphene oxide for electrocatalytic oxidation of methanol

PdCu nanoparticles supported on reduced graphene oxide nanosheets (PdCu/rGO) with uniform size distribution and dispersion are fabricated by a facile two-step reduction method. During the whole synthesis procedure, no capping agent or surfactant has been used. By varying the Pd/Cu molar ratio, electrocatalysts with different size distribution and dispersion of nanoparticles on graphene are prepared, and their electrocatalytic performance toward methanol oxidation reaction has been studied. It is concluded that the as-prepared electrocatalyst of Pd₂Cu₂/rGO, of which the Pd/Cu molar ratio is 1:1, exhibits the highest mass activity and most stable electroactivity. Compared to commercial Pd/C, the as-prepared Pd₂Cu₂/rGO also demonstrates 2.49 times higher mass activity and much more stable electroactivity. The excellent performance of the Pd₂Cu₂/rGO electrocatalyts is mainly due to the advantages of bimetallic synergistic effects and the supporting material of graphene. Owing to the advantages of high electroactivity, long stability, and cost-effectiveness, the as-prepared Pd₂Cu₂/rGO nanocomposites are promising anode electrocatalysts for direct methanol fuel cells.