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Corresponding Author

Rui-Zhi YANG(yangrz@suda.edu.cn)

Abstract

The electrochemically dealloyed Pt(Pd)-Cu catalysts were prepared by electrochemical dealloying of Cu3Pt(Pd) and their catalytic activities toward oxygen reduction reaction (ORR) were studied in 0.1 mol?L-1 HClO4 . solutions. The structural features of the dealloyed Pt(Pd)-Cu were revealed by synchrotron-based anomalous X-ray diffraction (AXRD) and surface X-ray scattering (SXS) at an atomic scale. We established a relationship between the structure and the catalytic activity by comparing the ORR activity and the structure of dealloyed Cu3Pt nanoparticles with similarly dealloyed Cu3Pt thin films and Cu3Pt(111). The enhancement in the activity of the dealloyed Pt(Pd)-Cu is mainly attributed to the strain change in the Pt(Pd) overlayer formed on the surface after dealloying. The strain is related to the thickness of Pt(Pd) overlayer, which is affected by the size of the material and the diffusion coefficient of the constituent element. The catalytic activity for ORR can be tuned by the strain in the surface layer of a catalyst.

Graphical Abstract

Keywords

oxygen reduction reaction, electrochemical dealloying, Pt(Pd)-Cu alloy, electrocatalyst

Publication Date

2012-04-28

Online Available Date

2012-01-19

Revised Date

2012-01-09

Received Date

2011-11-24

References

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