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Designing the low cost, active, durable, and alcohol-tolerant cathode catalysts towards the oxygen reduction reaction(ORR) is significant for the large-scale commercialization of direct alcohol fuel cells.Recently, Pd-based nanocrystals have attracted attention as Pt-alternative cathode catalysts towards the ORR in the alkaline electrolyte. Unfortunately, the pristine Pd-based nanocrystals lack the selectivity towards the ORR due to their inherent activity for the alcohol molecule oxidation reaction in the alkaline electrolyte. In this work, polyethyleneimine(PEI) modified Au Pd alloy nanocrystals with Au-rich Au Pd alloy cores and Pd-rich Pd Au alloy shells(AuPd@PdAu-PEI) are successfully synthesized using a traditional chemical reduction method in presence of PEI. The rotating disk electrode(RDE) technique is applied to evaluate the ORR performance of AuPd@PdAu-PEI nanocrystals. Compared with commercial Pd black,AuPd@PdAu-PEI nanocrystals show significantly enhanced activity and durability towards the ORR, and simultaneously exhibit particular alcohol tolerance towards the ORR in the alkaline electrolyte.
Designing the low cost, active, durable, and alcohol-tolerant cathode catalysts towards the oxygen reduction reaction (ORR) is significant for the large-scale commercialization of direct alcohol fuel cells. Revenuely, Pd-based nanocrystals have attracted attention as Pt-alternative cathode catalysts towards the ORR in the alkaline electrolyte. Unfortunately, the pristine Pd-based nanocrystals lack the selectivity towards the ORR due to their inherent activity for the alcohol molecule oxidation reaction in the alkaline electrolyte. In this work, polyethyleneimine (PEI) modified Au Pd alloy nanocrystals with Au-rich Au Pd alloy cores and Pd-rich Pd Au alloy shells (AuPd @ PdAu-PEI) are successfully synthesized using a traditional chemical reduction method in presence of PEI. The rotating disk electrode (RDE) technique is applied To evaluate the ORR performance of AuPd @ PdAu-PEI nanocrystals. Compared with commercial Pd black, AuPd @ PdAu-PEI nanocrystals show significantly enhanced activity and dura bility towards the ORR, and simultaneously show particular alcohol tolerance towards the ORR in the alkaline electrolyte.