Bimetallic PtPb for formic acid electro-oxidation

Bimetallic PtPb had been synthesized by arc-melted and then sintering treatment. The electro-oxidation of formic acid on PtPb was investigated at room temperature by cyclic voltammetry and chronoamperometry. The results are compared to those at a polycrystalline platinum electrode surface. It was found that PtPb Bimetallic was catalytically more active than pure platinum. Firstly, at the PtPb surface the peak potential for formic acid oxidation is shifted negatively by over 300 mV. Secondly, the current density at the PtPb electrode is dramatically higher than that for the Pt electrode. Thirdly, the ratio of the forward anodic peak current density (If) to the reverse anodic peak current density (I-b) for PtPb was much higher than that for the Pt electrode which indicated more intermediate carbonaceous species were oxidized to carbon dioxide in the forward scan on PtPb electrode surface. XRD and XPS technologies had been used to investigate the crystal structure and electron effect. It is proposed that formic acid decomposition on PtPb favors the reactive intermediate route and is not very much affected by the CO intermediate as compared to Pt. (c) 2006 Elsevier B.V. All rights reserved.