Synthesis and Electrocatalytic Activity of Au-Pd Alloy Nanodendrites for Ethanol Oxidation

Dendritic Au-Pd alloy nanoparticles were synthesized in high yield through the coreduction of HAuCl4 and K2PdCl4 in aqueous solutions by using hydrazine as a reducing agent. Relative compositions between Au and Pd at the particle surfaces as well as in bulk phases could be modulated by controlling the molar ratios between metal precursors in the feeding solutions. The formation of nanodendrites may be the result of the fast reduction rate of metal ions and subsequent fast, kinetically controlled growth of particles. The prepared alloy nanoparticles exhibit efficient electrocatalytic activities and stabilities toward ethanol oxidation in alkaline media. The enhanced electrocatalytic properties of dendritic particles can be attributed to the presence of a large number of active sites on their surfaces.