The corrosion and electrochemical behavior of pure aluminum in additive-containing alkaline methanol–water mixed solutions

The corrosion and electrochemical behavior of aluminum in inhibited and uninhibited 4 M KOH–methanol–water mixed solutions with a methanol/water volume ratio of 3:2 were investigated by means of hydrogen collection, polarization curve, galvanostatic discharge, and electrochemical impedance spectroscopy (EIS). The results of hydrogen collection and electrochemical experiments showed that the addition of ZnO can obviously inhibit the corrosion of aluminum in the 4 M KOH–methanol–water solutions, and its inhibition effect can be enhanced in the hydroxytryptamine (HT)-containing KOH solution. The results of scanning electron microscopy (SEM) and energy dispersive analysis of X-ray (EDAX) revealed that ZnO produces the inhibition effect by the formation of a zinc-containing deposit layer on the surface of aluminum, and the cooperative effect of ZnO and HT may improve the deposit of zinc. The results of galvanostatic discharge indicated that aluminum can present good electrochemical activity in the 4 M KOH–methanol–water solution with 0.2 M ZnO and 1.0 mL/L HT.     

Corrosion and electrochemical behaviors of pure aluminum in novel KOH‐ionic liquid‐water solutions

The corrosion and electrochemical behaviors of pure aluminum in KOH‐ionic liquid‐water solutions with variable volume ratios of water and the ionic liquid 1‐butyl‐3‐methyl imidazolium tetrafluoroborate (BMIMBF₄) were for the first time investigated by means of hydrogen collection, polarization curve, galvanostatic discharge, and electrochemical impedance spectroscopy (EIS). The results of hydrogen collection experiments showed that aluminum has a low corrosion rate in KOH‐BMIMBF₄‐H₂O solutions, and the corrosion rate decreases with increase in BMIMBF₄ content in the electrolytes. The results of electrochemical experiments revealed that aluminum is electrochemically active over a very wide potential window in the KOH‐BMIMBF₄‐H₂O solutions, and its electrochemically kinetic mechanism is similar to that in the corresponding aqueous solution; the increase in KOH and water contents in the electrolytes may improve the anodic dissolution performance of aluminum. It was found that aluminum presents excellent galvanostatic discharge performance in the 2.0 M KOH BMIMBF₄‐H₂O mixed solution with 60% water.     

锌酸盐对Zn在KOH溶液中腐蚀及电化学行为的影响

用电化学方法研究了锌酸盐对Zn在KOH溶液中腐蚀及电化学行为的影响,提出了K2Zn(OH)4在高浓度时对析氢反应的促进机制,并对观察到的实验现象进行了讨论     

Evaluation of nanometer-sized zirconium oxide incorporated Al—Mg—Ga—Sn alloy as anode for alkaline aluminum batteries

Zirconium oxide nanoparticles with 0.4 wt.% and 0.8 wt.% are incorporated into the Al—0.65Mg—0.05Ga— 0.15Sn (wt.%) alloy anode (base alloy) in order to improve the performance of the resulting anodes. Electrochemical characterization of the reinforced alloys was done by potentiodynamic polarization, electrochemical impedance spectroscopy and galvanostatic discharge and corrosion behavior was evaluated using self-corrosion rate and hydrogen evolution in 4 mol/L KOH solution. The surface morphology of the alloys was also studied using field emission scanning electron microscope (FESEM). The obtained results indicate that the base alloy shows high corrosion rate in 4 mol/L KOH solution by releasing 0.47 mL/(min·cm²) hydrogen gas, whereas the alloy containing 0.8 wt.% ZrO₂ provides the lowest hydrogen evolution rate by releasing 0.32 mL/(min·cm²) hydrogen gas. Furthermore, by increasing zirconium oxide nanoparticles, the corrosion current density of the aluminum anodes is decreased and their corrosion resistance increases significantly compared to the base alloy in alkaline solution. In addition, nanometer-sized zirconium oxide incorporated anodes exhibit the improved galvanic discharge efficiencies, so that 0.8 wt.% nano-zirconium oxide incorporated base alloy displays the highest power density and anodic utilization compared with the others in 4 mol/L KOH solution.     

Wasserstoffinduzierte Spannungsrißkorrosion an unverzinkten und verzinkten Baustählen

Hydrogen induced stress corrosion cracking of non galvanized and galvanized construction steels The processes of atmospheric corrosion and corrosion in collected water which may lead to hydrogen induced stress corrosion cracking of high-strength reinforcing steels in casing tubes before injection with concrete are discussed. Hydrogen uptake during corrosion occurs in weakly acid solutions as well as in neutral or alkaline aqueous solutions. The hydrogen uptake by proton discharge in acid solutions decreases with increasing pH of the electrolyte. Hydrogen can also be absorbed in neutral to weakly alkaline solutions if steels are plastically deformed and water reacts with the fresh iron surface. In alkaline solutions, hydrogen uptake is possible if, at the generally passivated steel surface, localized corrosion (pitting or crevice corrosion), local galvanic cells and a sufficient decrease in the pH of the pit electrolyte occurs. In the case of galvanized steels with damaged zinc layers, hydrogen uptake may result from the cathodic polarization of the free steel surface by zinc dissolution. The absorbed hydrogen interacts with the microstructure of the steels and weakens the bonds between the iron atoms. The influence of the microstructure of high-strength steels on the fracture behaviour is discussed on the basic of the so-called decohesion theory.     

Al-Mg-Sn基阳极材料在含ZnO碱性溶液中的电化学性能研究

研究了Al-0.5Mg-0.1Sn-0.1Si-0.02In (质量分数,%) 合金作为铝空气电池的阳极材料,在2 mol/L NaCl,4 mol/L NaOH,4 mol/L NaOH-0.2 mol/L ZnO,7 mol/L KOH 和 7 mol/L KOH-0.2 mol/L ZnO溶液中的腐蚀行为及电化学性能。结果表明,该合金在4 mol/L NaOH-0.2 mol/L ZnO和7 mol/L KOH-0.2 mol/L ZnO溶液中具有较好的综合电化学性能。该合金在2 mol/L NaCl,4 mol/L NaOH及7 mol/L KOH溶液中的溶解由电荷转移步骤控制,在4 mol/L NaOH-0.2 mol/L ZnO和7 mol/L KOH-0.2 mol/L ZnO溶液中的溶解由电荷转移及质量转移混合控制。相比于Zn在7 mol/L KOH溶液中的电化学性能,以该合金作为阳极材料,以4 mol/L NaOH-0.2 mol/L ZnO或7 mol/L KOH-0.2 mol/L ZnO溶液作为电解液的铝空气电池是可行的。     

Anodic Behaviour of Zinc in Potassium Hydroxide Solution: II.* Horizontal Anodes in Electrolytes Containing Zn(II)

Abstract

Equilibrium solubility data for ZnO in KOH are reported for KOH concentraiions up to 14M.

Results of passivation time determination for horizontally orientated zinc anodes In alkaline zincate electrolytes are reported. These results are correlated in the form: (i–i₁) t_p½ = k, where k and i₁ depend on [Zn(II)], [OH_?] and temperature. Passivation occurs when the [Zn(II)] at the anode is equivalent to the [OH?] of the electrolyte.

Overpotential–current density relationships indicate that the charge-transfer reactIon is complicated.     

席夫碱基季铵盐型双子表面活性剂对碱性锌电极电化学性能的影响

目的选择席夫碱基季铵盐型双子表面活性剂作为电解液添加剂,改善碱性锌电极的电化学性能,提高其耐蚀性能。方法通过电化学分析法,如失重法、塔菲尔极化曲线法、交流阻抗法等分析研究三种席夫碱基季铵盐型双子表面活性剂(D1、D2、D3)对锌电极电化学性能的影响,利用X射线光电子能谱(XPS)和扫描电子显微镜(SEM)研究在6 mol/L KOH电解液(饱和ZnO)浸泡48 h后,锌片表面的成分和形貌。结果室温下,缓蚀率随席夫碱基季铵盐型表面活性剂浓度升高而增加,当浓度进一步增大,缓蚀率变化不大。三种席夫碱基表面活性剂中,D3缓蚀能力最强,缓蚀率最高达95.67%,抑制腐蚀的效果顺序为:D3D2D1,属于抑制阳极型缓蚀剂。结论 D1、D2、D3作为碱性锌电极的电解液添加剂,可以有效减缓锌电极的腐蚀、变形、钝化及枝晶形成的能力,改善了碱性锌电极的电化学性能,D1、D2、D3适合作为碱性锌电池的缓蚀添加剂。     

全光亮碱性锌酸盐镀锌工艺研究

在碱性锌酸盐镀锌基础液中加入自制光亮剂XY-03A,研究成功了一种全光亮碱性锌酸盐镀锌工艺,确定了电镀工艺规范,采用霍尔槽试验探讨了主要成分对镀层质量的影响,检测了镀液和镀层性能,结果表明：所形成的锌镀层光亮度高,镀层结晶细致,与基体结合力好;镀液的分散能力、复盖能力、电流效率和镀层耐蚀性优于DE型镀锌工艺,具有较高的应用价值.     

Effects of Ca-substitution and surface treatment on electrochemical performances of Ml1.0- xCax Ni4.0Co0.6Al0.4 hydrogen storage alloy electrodes

１　ＩＮＴＲＯＤＵＣＴＩＯＮＮｉｃｋｅｌｍｅｔａｌｈｙｄｒｉｄｅ（Ｎｉ／ＭＨ）ｂａｔｔｅｒｉｅｓｈａｖｅａｔｔｒａｃｔｅｄｍｕｃｈａｔｔｅｎｔｉｏｎｂｅｃａｕｓｅｔｈｅｙｈａｖｅｈｉｇｈｅｒｅｎｅｒｇｙｄｅｎｓｉｔｙａｎｄｅｎｖｉｒｏｎｍｅｎｔａｌａｄｖａｎｔａｇｅｃｏｍｐａｒｅｄｗｉｔｈＮｉ／Ｃｄｂａｔｔｅｒｉｅｓ．ＭａｎｙｍｕｌｔｉｃｏｍｐｏｎｅｎｔＡＢ５ｔｙｐｅｈｙｄｒｏｇｅｎｓｔｏｒａｇｅａｌｌｏｙｓｈａｖｅｂｅｅｎｄｅｖｅｌｏｐｅｄｔｏｉｍｐｒｏｖｅｐｅｒｆｏｒｍａｎｃｅｓｏｆ…     

无汞扣式碱锰电池的安全性能

探讨电池配方和工艺参数对无汞扣式碱锰电池安全性能的影响,采用短路测试和过放电测试的方法研究各种工艺配方下电池的安全性能,通过实验研究了影响电池安全性能的各种因素,并确定最佳的工艺参数分别如下：负极与正极容量配比为0.9：1,KOH电解液浓度为43%（质量分数）,电解液中氧化锌的含量为7%,锌膏中的氧化锌用量为0.8%～1.0%,锌膏中电解液用量为锌粉量的40%～42%,锌膏中增稠剂用量为锌粉量的1%且其中聚丙烯酸钠与聚丙烯酸的质量比为6：4,锌膏中缓蚀剂用量为锌粉量的0.01%。在此工艺条件下制得的无汞扣式碱锰电池短路测试后不爆炸、过放电测试后尺寸变形不超过规定最大尺寸的0.12 mm。     

Influence of histidine as an electrolyte additive on the electrochemical performance of Al electrodes in 4.0 M KOH electrolyte

In this study, the influence of histidine as an electrolyte additive on the electrochemical performance of Al electrodes in 4.0 M KOH electrolyte is studied by measuring open-circuit potential–time curves, potentiodynamic polarization, potentiostatic oxidation, and electrochemical impedance spectroscopy. The surface morphology of Al electrodes is characterized by scanning electron microscopy. The results show that the battery performance is significantly improved by adding histidine. Samples with 50 mM histidine exhibit the highest corrosion resistance and discharging current density among all the specimens, with the corrosion current density (I_corr) being 7.471 mA/cm² and corrosion inhibition efficiency (η) being 43.33%.     

锌在KOH溶液中的腐蚀电化学行为

用电化学方法研究了锌在浓ＫＯＨ溶液中的电化学行为，得出了锌在浓碱液中的电化学反应机理。利用弱极化曲线拟合法得出了锌的腐蚀速度与ＫＯＨ浓度的关系。     

碱性溶液锌铁合金电沉积研究

在碱性锌酸盐溶液中电沉积获取 Fe0.4—0.8%的锌铁耐蚀合金镀层。探讨了镀液成分对合金含 Fe 量的影响,含 Fe0.4～0.8%的 Zn-Fe 合金镀层的耐蚀性优于普通镀层。讨论认为 Zn-Fe 合金的共沉积为异常共沉积。     

钙添加剂对可充锌电极性能的影响

通过直接化学反应法,化学共沉淀法以及物理混合方法在可充锌电极活性物质一氧化锌中掺入钙添加剂,研究了锌电极的充放电特必,放电容量及循环寿命等电化学性能,SEM分析表明直接化学反应法制备的样品是基面为四角形的薄片,化学共沉积法制备的样品是基面为六角形的多面体。XRD分析表面两种化学反应方法制备的样品均为锌酸钙晶体,由于制备过程中晶体优先生长方向不同而具有不同的形状。电极充放电实验结果表明,掺钙锌电极的电化学性能明显优于无钙锌电极,化学掺钙对锌电极电化学性能的改善优于物理混合掺钙。X射线照片表明由锌酸钙组成锌电极的表面活性物质分布较均匀,不掺钙的锌电极经多次充放电循环后电极表面已基本上没有活性物质。     

Double electrolyte sensor for monitoring hydrogen permeation rate in steels

An amperometric hydrogen sensor with double electrolytes composed of a gelatiniform electrolyte and KOH solution has been developed to determine the permeation rate of hydrogen atoms in steel equipment owing to hydrogen corrosion. The gelatiniform electrolyte was made of sodium polyacrylate (PAAS), carboxyl methyl cellulose (CMC) and 0.2 mol dm⁻³ KOH solution. The results show that the gelatiniform electrolyte containing 50 wt.% polymers has suitable viscosity and high electrical conductivity. The consistent permeation curves were detected by the sensor of the double electrolyte and single liquid KOH electrolyte, respectively. The developed sensor has good stability and reproducibility at room temperature.     

In对Al-Mg-Ga-Sn-(In)铝合金阳极组织及电化学性能的影响

在Al基体中添加Mg、Ga、Sn、In合金元素,通过正交试验设计了9组铝-空气电池阳极材料。采用动电位极化试验、析氢试验和恒电流放电试验对铝合金阳极的电化学性能进行优化,通过扫描电镜和能谱测试仪观察了合金的显微组织及成分。结果表明,没有添加In元素的1号合金(Al-0.5Mg-0.05Sn-0.05Ga)、5号合金(Al-Mg-0.1Sn-0.2Ga)和9号合金(Al-2Mg-0.2Sn-0.1Ga)铝阳极具有较差的放电性能和较高的自腐蚀速率,而添加0.05wt% In元素的7号铝阳极(Al-2Mg-0.05Sn-0.2Ga-0.05In)具有最好的放电电压(平均电位-1.968 V)和抗腐蚀性能 (自腐蚀速率0.193 mL·cm^-2·min^-1)。对比去腐蚀产物后的合金表面形貌,发现5号合金的腐蚀表面布满较深的腐蚀坑,这增加了铝合金的自腐蚀,而7号合金的表面具有较浅的腐蚀坑,这减缓了电解液中离子传递和自腐蚀速率。 因此,7号铝合金适合用作铝-空气电池阳极材料。     

Determination of Polarization resistance and corrosion rate by using pulse method,polarization curves and AAS

In this article, a presentation is made of the application of accelerated electrochemical methods in measuring the corrosion rates of electrolytic zinc coatings obtained from acid sulfate baths, with and without organic additives. The influence of deposition parameters on the corrosion resistance of zinc coatings in a deaerated 5% NaCl (pH = 6.4) solution at t = 25 and 35°C has been studied. The Tafel constants and polarization resistance have been calculated from the j-E curve in the vicinity of E_corr by means of computer and on the basis of the Mansfeld graphic method. The statistical relation between the corrosion current and the polarization resistance has been determined by the method of least squares. The dependence of the corrosion rate from the time of exposure to the corrosion medium has been studied by the pulse galvanostatic method and by direct analysis of the corrosion solution with absorption spectrometry. A good correlation of the results facilitates the practical application of this accelerated electrochemical method in the study of zinc and Zn-coatings resistant in electrolyte solutions and under conditions of atmospheric corrosion.     

吐温20对锌电极性能影响的掠射椭偏法研究

利用掠射式椭圆偏振光谱法现场考察了添加吐温20前后碱性介质中锌电极析氢性能的变化及其对锌电极性能的影响.试验结果表明:吐温20作为电解液添加剂能够影响1mol/dm3KOH溶液中锌电极上的析氢过程,随着吐温20添加浓度的增加,对析氢的抑制作用增加.掠射椭圆偏振参量与电极电位关系进一步表明吐温20对锌电极析氢过程的抑制作用属于几何覆盖效应,同时也表明碱性电解液中添加适宜浓度的吐温20可以有效地抑制阴极过程中锌电极的析氢反应、枝晶形成与电极变形.     

锌合金在KOH溶液中腐蚀性能的研究

用析氢量气法、动电位极化和交流阻抗技术对Ｚｎ－Ｉｎ合金、Ｚｎ－Ｐｂ合金在６ｍｏｌ／Ｌ ＫＯＨ溶液中的腐蚀性能进行了研究。结果表明,添加少量的Ｉｎ或Ｐｂ能明显地抑制Ｚｎ的腐蚀,并且Ｉｎ对Ｚｎ腐蚀的抑制作用更加显著;添加Ｐｂ对Ｚｎ在碱性溶液中的腐蚀机理基本无影响。而添加Ｉｎ的影响比较复杂。