熔盐电渗法制备代汞Zn-Ce合金电极的可行性研究

在NaCl AlCl3熔盐中 ,于无保护气氛条件下 ,用熔盐电渗法进行了锌表面渗铈 ,并用此技术制备了碱锰电池的代汞锌铈合金电极。实验发现 ,恒电流间歇滴定技术 (GITT)曲线中出现了 9个平台或拐点 ,所对应的电极电势分别为 - 5 1mV ,- 1 3 3mV ,- 1 5 4mV ,- 1 95mV ,- 2 46mV ,- 4 1 0mV ,- 5 2 3mV ,- 841mV ,- 1 1 5 9mV ,结合扫描电镜 (SEM )的能谱分析和相图证明形成了 9种锌铈合金 ;利用极化电阻的测定来检验锌合金在 40 %KOH溶液中的抗腐蚀性能 ,并采用正交试验法得到了最优试验条件 ,用最优试验条件制备的Zn Ce合金与纯锌的腐蚀电阻比较 ,结果表明锌与铈形成了耐蚀性的Zn Ce合金分布于锌的晶界 ,铈是碱锰电池负极的有效添加元素。

Study On the feasibility of preparing Zn-Ce alloy electrode substituting for mercury by means of molten salt electroosmosis

The cerium was interfused into zinc surface by electrolytic metallizing in NaCl AlCl 3 molten salt without protective atmosphere, thus Zn Ce alloy electrode substituting for mercury used in alkaline maganese dioxide battery was prepared. There were nine levels or turns in GITT(Galvanostatic Intermittent Titration Technique)curve, and the corresponding potential were -51 mV,-133 mV,-154 mV,-195 mV,-246 mV,-410 mV,-523 mV,-841 mV,-1159 mV respectively. As a result, nine kinds of zinc alloys were determined to be formed according to phase diagram and energy spectrum analysis of SEM. Furthermore,the corrosion resistant characteristics of the alloys were tested by polarization measurement in 40% KOH solution, and the optimum experiment condition was obtained by using orthogonalizing method. The corrosion resistant characteristics of the Zn Ce alloy prepared under the optimum condition and that of pure zinc were compared. The results show that the corrosion resistant Zn Ce alloy is formed in crystal lattice, and cerium is the effective additive element of negative electrode for alkaline manganese dioxide battery.