Synergistic Effect Of Pd–Au Bimetallic Surfaces In Au-covered Pd Nanowires Studied For Ethanol Oxidation

Highly ordered PdAu NWAs were successfully prepared by the combination of an AAOtemplate-electrodeposition and the Pd NWAs reacting with0.02mol L1HAuCl4in thefollowing replacement reaction. The synergistic effect of Pd–Au has been demonstrated byCVs with different cycles for ethanol electrooxidation on the PdAu15sNWA selectrode. Theresults show the existence of a synergistic effect of Pd–Au bimetallic surfaces in Au-coveredPd nanowires because the Es is0.712V on the PdAu15s NWAs electrode and123mV morenegative compared with that on the Pd NWAs electrode. At the potential of0.4V on theforward scan, the current density on the PdAu15sNWA electrode is45.7mAcm2and4.4timeshigher than that on the Pd NWAs electrode. The value of jpr/jpfon the PdAu15sNWAs is0.88which is smaller than that on the Pd NWAs which is1.15, showing the PdAu NWAselectrocatalyst should give the better poisoning-resistance and steady-state behavior forethanol oxidation. One hypothesis is that Pd acts as primary active sites for the catalyzing ofthe dehydrogenation of ethanol and CO-like intermediate species could be oxidized on the Ausurface to produce CO2or other products, releasing the active sites. The PdAuNWAsshowshigher activity and better poisoning-resistance behavior than the Pd NWAs for ethanolelectrooxidation.