The Pt@Au catalysts demonstrate remarkably high oxygen reduction reaction (ORR) activity compared with Pt/C catalysts. The ORR of Pt(2)@Au(1)/C and Pt(1)@Au(2)/C is 9.5 and 6.6 times that of Pt/C, respectively. This improvement is attributed to the electronic structure effect of the Au core on the Pt shell and introduction of PFSA.