Tungsten Carbide as Supports for Trimetallic AuPdPt Electrocatalysts for Methanol Oxidation
Ming Nie, Shengjuan Du, Qing Li, Matthew Hummel, Zhengrong Gu, Shun Lu
Abstract
Direct methanol fuel cell (DMFCs) is one of the best positioned toward widespread commercialization and the most viable alternative to lithium-ion batteries for portable applications. A major drawback of this technology is in large part related to the dependence on Pt-based electrocatalysts for methanol oxidation reaction (MOR) at the anode. To address this issue, low-Pt electrocatalysts are desired for keeping high performance of MOR. In this article, tungsten carbide (WC) enhanced trimetallic AuPdPt nanocomposite was prepared through the two-step method, i) intermittent microwave heating method (IMH) and ii) direct chemical reduction method. Trimetallic AuPdPt nanoparticles are dispersed well on the nanostructured WC, confirmed by scanning electron microscopy (SEM), energy X-ray diffraction spectroscopy (EDX), and transmission electron microscopy (TEM). The electrocatalytic performance of the as-synthesized nanocomposite for MOR was tested using cyclic voltammetry and chronopotentiometry in alkaline media. The results revealed that the WC enhanced trimetallic AuPdPt nanocomposites has better performance of MOR and stability than that of commercial Pt/C catalyst.