Scalable Preparation of the Chemically Ordered Pt-Fe-Au Nanocatalysts with High Catalytic Reactivity and Stability for Oxygen Reduction Reactions

Carbon-supported Au-PtxFey nanoparticles were synthesized via microwave heating polyol process, followed by annealing for the formation of the ordered structure. The structure characterizations indicate that Au is alloyed with intermetallic Pt-Fe nanoparticles and therefore the surface electronic properties are tuned. The electrochemical tests show that the microwave heating polyol process is more effective than oil bath heating polyol process for synthesizing the highly active catalysts. The introduction of trace Au (0.2 wt % Au) significantly improves the oxygen reduction reaction (ORR) catalytic activity of PtxFey catalysts. Au-PtFe/C-H (0.66 A/mg(Pt)) and Au-PtFe3/C-H (0.63 A/mg(Pt)) prepared in a batch of 10.0 g show significantly improved catalytic activities than their counterparts (PtFe/C-H and PtFe3/C-H) as well as commercial Johnson Matthey Pt/C (0.17 A/mg(Pt)). In addition, the as-prepared Au-PtFe/C-H and Au-PtFe3/C-H display highly enhanced stability toward the ORR compared to the commercial Pt/C. The superior catalytic performance is attributed to the synergistic effect of chemically ordered intermetallic structure and Au. This work provides a scalable synthesis of the multimetallic chemically ordered Au-PtxFey catalysts with high ORR catalytic performance in acidic condition.