中文摘要：

分别在酸性和碱性电解质中研究了界面合金化的纳米Ag承载Pt纳米结构催化剂Pt0.5^Ag-B／C（Pt／Ag原子比为O．5）对氧还原反应（ORR）的电催化特点．结果表明，该催化剂对ORR的半波电势（E1/2）与通常的Pt／C催化剂（E—TEK公司）相当，但前者的本征电催化活性是后者的近两倍．与未合金化的Pt0.5^Ag．A／C相比，在Pt0.5^Ag-B／C催化剂中形成的合金化的Pt／Ag界面不仅使ORR的E1/2正移，而且明显提高了贵金属Pt的分散度或利用率．

英文摘要：

An interfacially alloyed Pt-on-Ag nanostructure （Pto.sAAg-B/C） was loaded on Vulcan XC-72 carbon to make a cathode Pt0.5^Ag-B/C catalyst for the oxygen reduction reaction （ORR）. The electrocatalytic performance of this Pt0.5^Ag-B/C catalyst was measured by reference to its unalloyed counterpart Pt0.5^Ag-A/C and E-TEK Pt/C catalysts. The intrinsic activity of Pt in the Pt0.5^Ag-B/C catalyst was identified to be twice that in the E-TEK PUC catalyst although the half-wave potentials （E1/2） of the ORR curves over both catalysts were the same. Compared with the unalloyed Pt0.5^Ag-A/C catalyst, the alloying at the Pt/Ag interface in the Pt0.5^Ag-B/C catalyst gave a more positive E1/2 and also a significantly higher mass-specific activity of Pt for ORR.