Synthesis of Au/C catalyst with high electrooxidation activity

Au nanoparticles (AuNPs) supported on activated carbon (Au/C) were prepared by a modified chemical reduction method. The morphology, structure, surface chemical state and electro-oxidation activity of AuNPs were investigated by the transmission electron microscope (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV) and chronoamperometry. Results indicated that the Au/C catalyst possessed small AuNPs with a certain number of gold oxide species. This intrinsic property resulted in the high catalytic activity of the Au/C catalyst for the electro-oxidation of alcohol molecule. The peak values of anodic mass-specific current densities on AuNPs reached 69.5, 442 and 660 mA mg−1Au, respectively in 0.1 M KOH solutions with 6 M methanol, 2 M ethanol and 0.5 M ethylene glycol.

► A series of Au/C catalysts are synthesized by a deposition-reduction process.
► Alkalescent medium is suitable for preparing the Au/C catalyst with high Au loading.
► Excessive KBH4 can employ as a sedimentation promoter for colloid AuNPs.
► Au/C catalyst shows good activity and poison tolerance for the ethanol oxidation.