Thermodynamics and Kinetics of Platinum Dissolution from Carbon-Supported Electrocatalysts in Aqueous Media under Potentiostatic and Potentiodynamic Conditions

被引：81

作者：

Ahluwalia, Rajesh K. ^{[1
]}

Arisetty, Srikanth ^{[1
]}

Wang, Xiaoping ^{[1
]}

Wang, Xiaohua ^{[1
]}

Subbaraman, Ram ^{[1
]}

Ball, Sarah C. ^{[2
]}

DeCrane, Stacy ^{[1
,3
]}

Myers, Deborah J. ^{[1
]}

机构：

[1] Argonne Natl Lab, Argonne, IL 60439 USA

[2] Johnson Matthey Technol Ctr, Reading RG4 9NH, Berks, England

[3] Kettering Univ, Flint, MI 48503 USA

来源：

JOURNAL OF THE ELECTROCHEMICAL SOCIETY | 2013年 / 160卷 / 04期

关键词：

PROTON-EXCHANGE MEMBRANE; PARTICLE-SIZE; DURABILITY; INSTABILITY; MECHANISM; ELECTRODE; SURFACES;

D O I：

10.1149/2.018306jes

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

070208 [无线电物理];

摘要：

The stability of dispersed high surface area carbon-supported platinum nano-particle electrocatalysts (Pt/C) was investigated as a function of particle size (mean diameters of 1.9, 3.2, 7.1, and 12.7 nm) and oxide coverage under potentiostatic and potentiodynamic conditions in aqueous perchloric acid electrolyte. A non-ideal solid solution theory was formulated to explain the observed dependence of the equilibrium dissolved Pt concentration on potential, Pt particle size, and oxide coverage, as inferred from cyclic voltammetry measurements. The activities of Pt and PtOx in Pt-PtOx solid solutions were correlated with the oxide coverage and Pt particle size. The theoretical framework was also used to determine the rate constants for Pt dissolution and PtOx formation and reduction. The results from the kinetic model were found to be consistent with the measured Pt dissolution for triangle potential cycles with different upper and lower potential limits and scan rates. (C) 2013 The Electrochemical Society. [DOT: 10.1149/2.018306jes] All rights reserved.

引用

页码：F447 / F455

页数：9

共 30 条

[1]

Analytical TEM study of Pt particle deposition in the proton-exchange membrane of a membrane-electrode-assembly [J].