VOLUME 64 : 2016

This study aims to utilize pulse electrodeposition to synthesize tin/palladium/exfoliated graphene oxide (Sn/Pd/EGO) catalyst composite as anode material for ethanol oxidation reaction (EOR) which finds significant application in Direct Ethanol Fuel Cell (DEFC) application. The electrocatalytic activity of the prepared catalysts towards ethanol oxidation was evaluated using cyclic voltammetry in 1 M ethanol in 0.1 M NaOH. Cyclic voltammetry showed that the addition of Sn to Pd improved the catalytic activity of Pd towards EOR in alkaline solution. The bimetallic Sn/Pd catalyst on glassy carbon electrode (Sn/Pd/GCE) showed a higher catalytic activity with a peak current density of 28.1 mA cm-–2, compared to Pd/GCE (23.39 mA cm–2). The electrocatalytic activity of bimetallic Sn/Pd catalyst further improved when EGO was used as a support (Sn/Pd/EGO) with a peak current density of 36.7 mA cm–2. Atomic force microscopy revealed that the catalysts were deposited on the edges of the graphene sheets forming bright clusters with dark fringes on the middle of the structure. X-ray photoelectron spectroscopy confirmed the presence of Pd and Sn metals and their oxides. This study demonstrates that pulse electrodeposition could offer a much simpler and faster approach in the development of high performance catalysts for EOR.

Keywords: direct ethanol fuel cells, graphene, Sn/Pd, AFM, XPS, pulse electrodeposition