▎ 摘　　要

Pd/graphene composites were successfully prepared in H2O/TX-100/[BMIM] PF6 microemulsion in which PdCl62- ions were reduced in situ by TX-100 and graphene oxide was reduced by hydrazine hydrate. In the confinement region of the microemulsion, ultrafine Pd nanoparticles (NPs) supported on graphene composites were successfully prepared. The as-prepared composite materials of Pd NPs and graphene were characterized by scanning electron microscopy, transmission electron microscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction. It is demonstrated that the size distribution of Pd NPs is narrow, with an average size of 4 nm. The Pd/graphene composites were tested as electrocatalysts for application in fuel cells. Cyclic voltammetry and chronoamperometry measurements show good electrocatalytic performance of the composite materials for oxidation of ethanol in alkaline medium.