Electrodeposition of magnesium from the eutectic LiCl–KCl melt
Electrodeposition of magnesium from the eutectic LiCl–KCl melt
复制标题
DOI：
10.1007/s10800-004-1761-6
复制
发表时间：
2004-12
影响因子：
2.9
通讯作者：
A. M. Martínez;B. Børresen;G. Haarberg;Y. Castrillejo;R. Tunold
中科院分区：
文献类型：
--
作者：
A. M. Martínez;B. Børresen;G. Haarberg;Y. Castrillejo;R. Tunold
以钨为正极材料，研究了在含不同浓度氯化镁的低共晶LiCl-KCl混合物(58-42mol%)中电沉积镁的行为。温度在镁的熔点(983K)上下变化。采用循环伏安法、计时电位法和计时电流法等电化学技术对该体系进行了表征，并研究了镁相的形核和生长。利用上述电化学技术，观察到了固体镁沉积的宏观生长过程。发现液态镁沉积在没有引起比表面积显著增加的情况下增长。这可能与锂的共沉积和锂-镁液体溶液的形成以及每种情况下阴极沉积的界面性质不同有关。在镁熔点以下或更高的温度下，锂在预沉积的镁上沉积，分别形成锂镁固体合金或液态锂镁溶液。用不同的电化学方法测定了镁离子的扩散系数。所得数值反映了固体镁矿床中矿床宏观生长的影响。
Electrodeposition of magnesium in the eutectic LiCl--KCl mixture (58--42 mol%) containing different MgCl2concentrations was studied using tungsten as cathode material. The temperature was varied above and below the melting point of magnesium (983 K). Electrochemical techniques such as cyclic voltammetry, chronopotentiometry and chronoamperometry were employed in order to characterise the system and study nucleation and growth of the magnesium phase. With all the electrochemical techniques above mentioned, macroscopic growth of the solid magnesium deposit was observed. Liquid magnesium deposits were found to grow without giving rise to a significant increase in surface area. This may be related to lithium co-deposition and formation of Li--Mg liquid solution and the differences in interfacial properties of the cathodic deposits obtained in each case. The deposition of lithium on pre-deposited magnesium leads to the formation of Li--Mg solid alloys or to a liquid Li--Mg solution at temperatures below or above the melting point of magnesium, respectively. The diffusion coefficient of magnesium ions was determined by different electrochemical techniques. The values obtained showed the effect of macroscopic growth of the deposit in the case of solid magnesium deposits.