K-Edge X-ray Absorption Fine Structure Analysis of Pt/Au Core鈥揝hell Electrocatalyst: Evidence for Short Pt鈥揚t Distance
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- 作者：Takahiro Kaito ; Hisashi Mitsumoto ; Seiho Sugawara ; Kazuhiko Shinohara ; Hiromitsu Uehara ; Hiroko Ariga ; Satoru Takakusagi ; Yoshikiyo Hatakeyama ; Keiko Nishikawa ; Kiyotaka Asakura
- 刊名：Journal of Physical Chemistry C
- 出版年：2014
- 出版时间：April 24, 2014
- 年：2014
- 卷：118
- 期：16
- 页码：8481-8490
- 全文大小：511K
- 年卷期：v.118,no.16(April 24, 2014)
- ISSN：1932-7455
文摘
A carbon-supported Pt-shell Au-core electrocatalyst (Pt/Au/C) was prepared by sequential deposition of Pt ions on the surface of Au nanoparticles supported on carbon. The area-specific activity of the oxygen reduction reaction (ORR) for the prepared Pt/Au/C in 0.1 M HClO4 aqueous solution was approximately 2 times higher than that for a commercial carbon-supported Pt electrocatalyst (Pt/C). The core鈥搒hell structure was confirmed using electrochemical methods and Pt and Au K-edge X-ray absorption fine structure (XAFS) analysis. XAFS analyses indicated that the Pt鈥揚t bond distance for the Pt/Au/C catalyst was shorter than that for Pt foil and the Pt/C catalyst. In addition, the Au鈥揂u distance was much shorter than that for Au foil. The reason for the high ORR activity of Pt/Au/C is considered to be shorter Pt鈥揚t bond distance as compared to that of Pt/C.