Impedance study of formic acid oxidation on platinum electrodes

被引：53

作者：

Seland, Frode ^{[1
]}

Tunold, Reidar ^{[1
]}

Harrington, David A. ^{[2
]}

机构：

[1] Norwegian Univ Sci & Technol, Electrochem Grp, Dept Mat Sci & Engn, NO-7491 Trondheim, Norway

[2] Univ Victoria, Dept Chem, Victoria, BC V8W 3V6, Canada

来源：

ELECTROCHIMICA ACTA | 2008年 / 53卷 / 23期

基金：

加拿大自然科学与工程研究理事会;

关键词：

impedance; formic acid; oxidation; platinum; methanol; AC voltammetry; EIS; bifurcation; oscillation;

D O I：

10.1016/j.electacta.2007.12.021

中图分类号：

O646 [电化学、电解、磁化学];

学科分类号：

081704 ;

摘要：

The electrooxidation of formic acid on polycrystalline platinum electrodes in sulphuric acid is studied by a dynamic impedance method. Impedance spectra in the frequency range 0.7 Hz to 20 kHz, assembled from ac voltammograms, are interpreted in terms of a mechanism with three adsorbed species. although one of these may be free sites. The spectra show evidence for incipient oscillations in two potential regions, and observed oscillations were related to these spectra. The zeroes of the interfacial impedance were directly extracted from suitable equivalent circuits in distinct potential regions where oscillations may be triggered. The observation of only real zeroes of the interfacial impedance eliminates the possibility of pure potentiostaticoscillations arising from chemical reasons alone, and therefore potential is an essential variable. (c) 2007 Elsevier Ltd. All rights reserved.

引用

页码：6851 / 6864

页数：14

共 61 条

[1]

[Anonymous], THESIS NORWEGIAN U S

[2] THE ELECTROOXIDATION OF CO - A TEST REACTION IN ELECTROCATALYSIS [J].