Design of Au Surface‐doped PtFe Catalyst to Modulate Oxygen Binding Energy for Highly Efficient Oxygen Reduction Reaction

Abstract As ideal cathode catalysts for proton exchange membrane fuel cells (PEMFCs), the oxygen reduction reaction (ORR) activity and durability of Pt‐based alloys can be improved further. This study presents the catalyst with Au doping on the surface of an ordered PtFe alloy (Au‐PtFe/C) utilizing a synergistic process of microwave reduction and chemical replacement, as well as the reorganization of a Pt‐rich surface using acid etching and high temperature annealing. Physical characterization indicated that the oxygen binding energy on the surface of Au‐PtFe/C was more effective at promoting the ORR reaction than commercial Pt/C, which contributes significantly to its enhanced activity. Further electrochemical tests revealed that the Au‐PtFe/C catalyst exposes abundant active sites for ORR, with mass and specific activity up to 12 and 8 times that of commercial Pt/C, respectively. Additionally, the catalyst demonstrated remarkable durability following 10,000 cycles of accelerated durability tests (ADT) in acidic circumstances. In PEMFC test, the single cell with an Au‐PtFe/C cathode also performed admirably when compared with commercial Pt/C. Owing to its facile synthesis, low cost, and exceptional performance, this bimetal‐doped ordered Pt‐based alloy has the capability to be a promising component in fuel cells commercialization.