▎ 摘　　要

Pd and PdxNi nanoparticles have been supported on reduced graphene oxide (Pd/rGO and PdxNi/rGO) by using the microwave-assisted heating method in glycol. The morphology, composition and electrochemical performance have been characterized by TEM, XRD, XPS and electrochemical methods. The XRD and XPS results show that there are no PdNi alloy particles formed in PdxNi/rGO and the composites exist mostly in the form of Pd-0 and NiOOH species. The electrochemical results reveal that PdxNi/rGO synthesized from the feeding source of Pd and Ni with an atomic ratio of 4:1 exhibits higher activity, better stability and smaller electron transfer resistance toward formic acid electro-oxidation compared with commercial Pd/C, Pd/rGO and other PdxNi/rGO samples. The excellent electrocatalytic performance indicates that the addition of appropriate amount of Ni can greatly enhance the activity and stability of Pd catalysts for formic acid oxidation.