In situ assembly of ultrafine AuPd nanowires as efficient electrocatalysts for ethanol electroxidation

Abstract

Improving the catalytic activity and durability of the ethanol oxidation reaction (EOR) is crucial for realizing the commercialization of direct ethanol fuel cells (DEFCs). Herein, we design a facile route to fabricate AuPd nanowires as highly efficient electrocatalysts toward ethanol oxidation reaction (EOR), where AuPd nanowires were in-situ assembled through the co-reduction of HAuCl4 and PdCl2 in aqueous solution in the presence of Triton X-114 and with potassium borohydride as the reducing reagent. The surface microstructure and composition of AuPd alloyed nanowires with the diameter of 4 nm were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and high resolution-transmission electron microscopy (HR-TEM). Among the AuPd NWs series, Au8Pd3 NWs demonstrated the best electrocatalytic activity (mass activity 10,570 mA mg−1Pd) and enhanced durability for ethanol electroxidation (retained 54% after 300 cycles) among the samples. The enhanced activities in EOR can be ascribed to the synergic electronic and structural effects of AuPd NWs. This work can provide a feasible method to boost Pd-alloy based electrocatalysts for EOR in direct ethanol fuel cells.