Effect of silicate on passive films anodically formed on iron in alkaline solution as studied by electrochemical impedance spectroscopy

被引：47

作者：

Amaral, ST

Muller, IL

机构：

[1] Univ Fed Rio Grande Sul, Inst Chem, BR-91501970 Porto Alegre, RS, Brazil

[2] Univ Fed Rio Grande Sul, Dept Met, Porto Alegre, RS, Brazil

来源：

CORROSION | 1999年 / 55卷 / 01期

关键词：

capacitance; charge-transfer resistance; electrochemical impedance spectroscopy; inhibitors; iron; passivation; silica; sodium hydroxide;

D O I：

10.5006/1.3283960

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Studies using electrochemical impedance spectroscopy (EIS) were carried out on an iron disk electrode in 0.01 mol/L sodium hydroxide (NaOH) + x ppm silica (SiO2) (x = 250, 500, and 750 ppm) polarized at 300 mV(SCE) to determine the effect of silicate on passive films anodically formed on iron in alkaline solutions. EIS proved silicate increased film resistance (R-f), decreased its capacitance (C), and affected the kinetics of interfacial electrochemical reactions, leading to an increase in the charge-transfer resistance (R-t), which depended upon silicate concentration and polarization time.

引用

页码：17 / 23

页数：7

共 44 条

[1] A COMPARATIVE ELECTROCHEMICAL AND ELLIPSOMETRIC STUDY OF IRON ELECTRODES IN DIFFERENT ALKALINE ELECTROLYTES [J].