Electrochemical Quartz Crystal Microbalance Study on Dissolution of Platinum in Acid Solutions

• SUGAWARA Yuu

  Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology

• YADAV Amar Prasad

  Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology

• NISHIKATA Atsushi

  Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology

• TSURU Tooru

  Department of Metallurgy and Ceramics Science, Tokyo Institute of Technology

Abstract

The influence of chloride ion on the oxidation and dissolution of platinum has been studied by using Electrochemical Quartz Crystal Microbalance (EQCM) in combination with Inductively Coupled Plasma (ICP) analysis to clarify the deterioration mechanism of platinum catalyst in the Polymer Electrolyte Fuel Cell (PEFC). Platinum was electroplated on an Au-QCM electrode in 2% H₂PtCl₆ solution and used as the working electrode. A mass gain of the platinum electrode was observed during anodic polarization in 0.5 M H₂SO₄ solution ([Cl⁻] free solution) due probably to the formation of Pt oxide. The oxide film was not stable in the whole range of potential used in this study. On the other hand, a mass loss due to the dissolution of Pt as chloride complex ions was observed in more positive potentials than 0.85 V vs. SHE in chloride-containing solutions. As the chloride concentration increased, platinum showed a higher dissolution rate with the formation of chloride complexes, PtCl₄²⁻ and PtCl₆²⁻. The amount of dissolved PtCl₆²⁻ tended to increase with the increase of anodic potential limit. The EQCM results revealed that the dissolution of Pt was accelerated when potential was cycled between cathodic and anodic limits. The ICP analysis of the solution after anodic polarization supported the results obtained by EQCM.

Journal

• Electrochemistry

  Electrochemistry 75 (4), 359-365, 2007

  The Electrochemical Society of Japan

Keywords

• PEFC
• Platinum Dissolution
• EQCM
• Pt Oxide

Details

• CRID: 1390282681473853568
• NII Article ID: 10018415915
• NII Article ID: 130002150865
• NII Book ID: AN00151637
• DOI: 10.5796/electrochemistry.75.359
• COI: 1:CAS:528:DC%2BD2sXkt1OktLg%3D
• ISSN: 21862451
• ISSN: 13443542
• ISSN: http://id.crossref.org/issn/13443542
• NDL BIB ID: 8780829
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I8780829
• Web Site: https://www.jstage.jst.go.jp/article/electrochemistry/75/4/75_4_359/_pdf
• Text Lang: en
• Data Source:
  • JaLC
  • NDL
  • Crossref
  • CiNii Articles
• Abstract License Flag: Allowed