Preparation and characterization of palladium-nickel on graphene oxide support as anode catalyst for alkaline direct ethanol fuel cell

Abstract

A catalyst consisting of palladium – nickel supported on exfoliated graphene oxide (PdNi/EGO) composite was synthesized. The catalytic activity was tested for ethanol oxidation reaction (EOR) in half-cell using cyclic voltammetry (CV) and subsequently it was used as an anode material in a direct ethanol fuel cell (DEFC). Transmission Electron Microscopy showed the catalyst particles are uniformly dispersed on the surface of graphene oxide with the particle size ranging from 3 to 6 nm. X-ray Photoelectron Spectroscopy analysis of catalysts revealed that the surface consisting of mostly Pd, PdO, Ni(OH)2, and NiOOH. CV and chronoamperometry measurements demonstrated higher electrocatalytic activity and stability for PdNi/EGO in the alkaline medium than the unsupported PdNi and carbon black-supported PdNi (PdNi/C) catalysts. A single cell anion exchange membrane DEFC constructed with a PdNi/EGO anode catalyst showed a maximum power density of 16.6 m Wcm−2 at 50 °C, which is higher than the unsupported PdNi, PdNi/C, and commercial Pd/C catalyst. © 2016 Elsevier B.V.