Bimetallic palladium-gold nanoparticles synthesized in ionic liquid microemulsion

The palladium and gold precursors were dissolved in dispersive and continuous phase of ionic liquid microemulsion (H2O/Triton X-100 (TX-100)/1-butyl-3-methylimidazolium hexafluorophosphate), respectively. [PdCl6](2-) ions were reduced in situ by TX-100 in dispersive phase (H2O) to prepare Pd nanoparticles (NPs) and then [AuCl4](-) crossed through the interface film and reacted with the as-prepared Pd NPs to form Pd4Au NPs. The as-prepared Pd4Au NPs were characterized by transmission electronic microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, and ultraviolet-visible spectroscopy. The as-prepared Pd4Au NPs suspension and carbon nanotubes (CNTs) suspension were vigorously stirred to prepare the electrocatalyst supported on the CNTs with a total metal loading of 20 wt.% (denoted by Pd4Au/CNTs). Cyclic voltammetry and chronoamperometry tests show that the Pd4Au/CNTs are very promising for the oxidation of ethanol in alkaline medium. The result can be attributed to the synergistic effect between Pd and Au during the catalytic process.