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Pt-WOx/C catalysts containing 10 wt.% and 20 wt.% platinum per carbon are prepared by three different two-step impregnation/chemical (ethylene glycol-EG,NaBH4,and HCOOH) reduction methods in acidic conditions of pH<1.The Pt-WOx nanoparticles prepared by impregnation/EG reduction method present the best distribution and morphology with mean diameter of 3.3 nm determined from highresolution transmission electron microscope (HRTEM) images,the largest specific electrochemical surface area and the highest anodic peak current densities determined by Cu underpotential deposition experiment (Cu-UPD),cyclic voltammetry (CV) and linear sweep voltammetry (LSV).Its specific electrochemical surface area is 0.61 cm2/mgPt,1.6 and 10.2 times larger than those of the catalysts prepared by impregnation/NaBH4 and impregnation/HCOOH reduction methods,respectively.Its anodic peak current densities for the oxidation of ethanol during the positive potential sweep are 7.85 mA/mgPt,1.4 and 5.2 times higher than those of the catalysts prepared by the other methods,respectively.In addition,the Pt-WOx/C catalyst prepared by impregnation/EG reduction method containing 20 wt.% platinum per carbon shows 2.1 times higher anodic peak current densities than those containing 10 wt.% platinum per carbon,while the catalysts prepared by the other two impregnation/chemical reduction methods show decreased anodic peak current densities than those containing 10 wt.% platinum per carbon.X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD) analyses show that the platinum and tungsten in the 20 wt.% Pt-WOx/C catalyst prepared by impregnation/EG reduction method are mainly in metal state with face centered cubic (f.c.c.) structure and +VI oxidation state,respectively.