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arXiv · 1209.6629

Evaluating the role of Lead In A Novel Ternary Catalysts For DMFCs

Aditi Halder·Qingying Jia·Matthew Trahan·Sanjeev Mukerjee
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Abstract

The current density at lower potential is highly desirable in fuel cell technology and crucial center point for designing a new catalyst. By alloying platinum with various other metals, the improvisation of the fuel cell catalyst has achieved a lot of attention and interests. In this article, a novel porous ternary alloy PtPb@Ru as anode catalysts for direct methanol fuel cell had been synthesized by micro-emulsion technique. The catalysts had been characterized by various spectroscopic and microscopic techniques. The activity and durability of the catalysts had been tested by running cyclic voltammetry in 0.1 M HClO4 and 1M Methanol. To explain the many fold increase in current density of the PtPb@Ru catalysts in comparison to the commercial available PtRu catalysts, in situ X-ray absorption spectroscopy (XAS) measurements, at the PtL3 edge (XANES and EXAFS) were carried out on the PtPb@Ru catalysts in an electrochemical cell. The down-shift in the d-band center of platinum observed in the XAS study, might be responsible for the better activity and high current density observed here.

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Aditi Halder, Qingying Jia, Matthew Trahan, Sanjeev Mukerjee. 2012-09-28. Evaluating the role of Lead In A Novel Ternary Catalysts For DMFCs. https://arxiv.org/abs/1209.6629

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