文献类型：期刊文献

英文题名：Mechanism of formation of anodic excursion peaks on lead electrode in sulfuric acid

作者：Zhong, Juhua[1];Zhang, Bo[1,1,2];Cheng, Zhenmin[2]

机构：[1]E China Univ Sci & Technol, Dept Phys, Shanghai 200237, Peoples R China;[2]E China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2011

卷号：196

期号：13

起止页码：5719

外文期刊名：JOURNAL OF POWER SOURCES

收录：;EI(收录号：20111813947455);WOS:【SCI-EXPANDED(收录号:WOS:000291144000046)】；

语种：英文

外文关键词：Lead electrode; Anodic excursion peak; Nonstoiometric lead oxide; Passivated lead sulfate

摘要：Potential step and linear sweep voltammetry are proposed in combination for the anodic excursion peaks (AEPs) measurement of lead in sulfuric acid during cathodic scanning in the positive potential range. The overall procedure of measurement is composed of three steps. The first one is to polarize the lead electrode with negative potential, which is necessary for passivated PbSO(4)(O) formation. Then, the polarization potential is stepped to positive to make sure that pure Pb could be oxidized to produce PbO(n) intermediate. Finally, a low-rate cathodic linear sweep voltammetry measurement is conducted in a small potential range. Four AEPs have been observed without reduction of PbO(2) to PbSO(4), which is in confliction with the conventional understanding that AEPs would appear accompanying with a large reduction peak for PbO(2) discharge. A new mechanism is therefore proposed that AEPs corresponds to the oxidation of PbO(n) intermediate in the cathodic scanning, so AEPs can be used to indicate the difficulty for the oxidation of Pb to PbO(2), and could be applied to characterize the corrosion resistance of lead alloy grid in the positive plate of a lead-acid battery. (C) 2011 Elsevier B.V. All rights reserved.