Quaternary Pt2Ru1Fe1M1/C (M=Ni, Mo, or W) catalysts for methanol electro-oxidation reaction

Quaternary Pt2Ru1Fe1M1/C (M=Ni, Mo, or W) catalysts were investigated for the methanol electro-oxidationreaction (MOR). Electrocatalytic activities of the quaternary catalysts for CO electro-oxidation were studied viaCO stripping experiments, and the Pt2Ru1Fe1Ni1/C and Pt2Ru1Fe1W1/C catalysts exhibited lowered on-set potentialcompared to that of a commercial PtRu/C catalyst. MOR activities of the quaternary catalysts were determined by linearsweep voltammetry (LSV) experiments, and the Pt2Ru1Fe1W1/C catalyst outperformed the commercial PtRu/C catalystby 170 and 150% for the mass and specific activities, respectively. X-ray photoelectron spectroscopy (XPS) wasemployed to analyze surface oxidation states of constituent atoms, and it was identified that the structure of the synthesizedcatalysts are close to a nano-composite of Pt and constituent metal hydroxides and oxides. In addition, the XPSresults suggested that the bi-functional mechanism accounts for the improved performance of the Pt2Ru1Fe1Ni1/C andPt2Ru1 Fe1W1/C catalysts.