▎ 摘　　要

In recent years, graphene/metal nanocrystal hybrids have attracted tremendous attention in catalysis and electrocatalysis. This work demonstrates a surfactant-free coprecipitation/coreduction method to synthesize graphene-supported nanocrystalline PdCu (PdCu/GN) hybrids with high alloying degree. The strong interaction between graphene oxide and metal hydrates results in uniform precipitation on the graphene oxide surface, which plays a critical role in excellent dispersion and high alloying degree of PdCu nanocrystals. Cyclic voltammetry and chronoamperometry measurements show that nanocrystalline PdCu/GN hybrids have higher activity and durability than commercial Pd/C catalyst for the formic acid oxidation reaction.