Impedance study of formic acid oxidation on platinum electrodes
Impedance study of formic acid oxidation on platinum electrodes
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DOI：
10.1016/j.electacta.2007.12.021
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发表时间：
2008-10
影响因子：
6.6
通讯作者：
F. Seland;R. Tunold;D. Harrington
中科院分区：
文献类型：
--
作者：
F. Seland;R. Tunold;D. Harrington
采用动态阻抗法研究了硫酸中甲酸在多晶铂电极上的电氧化反应。由交流伏安图组成的频率范围 0.7Hz 至 20kHz 的阻抗谱根据三种吸附物质的机制进行解释，尽管其中一种可能是自由位点。光谱显示了两个潜在区域中初期振荡的证据，并且观察到的振荡与这些光谱相关。界面阻抗的零点直接从可能触发振荡的不同电位区域中的合适等效电路中提取。仅观察界面阻抗的实零点消除了仅由化学原因引起的纯恒电位振荡的可能性，因此电位是一个重要变量。
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 0.7Hz to 20kHz, 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 potentiostatic oscillations arising from chemical reasons alone, and therefore potential is an essential variable.