Study On The Electrochemical Behavior Of Zinc Electrodes Embellished In Alkaline Media

Zinc has many characteristics such as good discharge reversibility, less proper of electrochemistry, spare dissolve of anode, and rich resources. Therefore, it has been widely used in many fields. Because of its good electricity performance, zinc has been especially noticed that it can be used as the cathode material. However, there are still some disadvantages in zinc electrode, such as metamorphose dendritic growth, erosion, passivation etc. So it is very important to choose and discuss the electrochemical behavior and electrode performance of zinc electrode influenced by adding additives.In this paper, graze ellipsometry, cyclic voltammetry, current step and potential polarization method have been used to study the corrosion behavior of zinc in alkaline electrolytes with adding Bi3+, La3+, Ce4+ and Tween20, Tween60, Tween80. The influence of varies inhibitors on the behavior of corrosion and absorption of zinc electrode has been investigated. Bi3+, La3+, Ce4+ accelerate the dissolving of Zinc during process of anode reaction has been revealed. Bi3+ is the best additive to inhibit zinc dendritic growth and shape change of zinc electrode; the series of Tween inhibitors belong to admixture control inhibitors has also been revealed. It's absorption isotherm followed Freundlich isotherm equation. The anodic dissolution, cathodic hydrogen evolution, zinc dendritic growth and shape change of zinc electrode are suppressed by adding to these Tween inhibitors with certain concentration. The inhibition mechanism of Tween20 in any concentration studied is attributed to a covering effect, and that's of Tween60 is attributed to a negative catalytic effect. The experiment of graze ellipse has proved that Tween80's inhibition mechanism exist negative catalytic effect. It is attributed to a covering effect in lower concentration (<10-3g·dm-3) and is replaced by a negative catalytic effect in higher concentration (>10-3g·dm-3). Moreover, the paper has revealed that the structure of non-polarity group of inhibitor's molecule has an obvious influence on the effect of inhibition. Under the condition of suitable solubility, better effect of inhibition by using the molecule with longer carbon chain saturated can be obtained.