Analysis on the Wetting Behavior of Mercury to Zinc in a KOH Solution.

进行了锌在KOH溶液中的阳极溶解试验。溶解速率依次为（0001）单晶面、多晶面和（1100）单晶面。有人提出溶解速率取决于平面的原子密度。在薄而均匀地包裹锌层的条件下，少量的汞对锌在KOH溶液中的自溶有很大的阻碍作用。因此，在锌阳极上镀镀薄而均匀的汞是降低碱性电池中汞含量的关键。采用扩散系数（S= γ KOH/Zn - (γ Hg/Zn + γ KOH/Hg)）评价了汞在KOH溶液中对锌的润湿作用。通过测量KOH溶液的表面张力和Hg与KOH溶液之间的界面张力来计算S的值。在KOH- zn -Hg体系中S的值始终为正，并随着体系中KOH浓度的增加而增加。结果表明，要在高KOH浓度的溶液中对锌粉进行镀汞，以达到薄而均匀的镀汞效果。

Anodic dissolution tests of zinc in KOH solutions were carried out. Dissolution rates became faster in order of (0001) single crystal plane, poly-crystaline plane and (1100) single crystal plane. It was suggested that dissolution rates depended on the atomic density of the plane. Very small amount of Hg took a big role to prevent the self-dissolution of zinc in a KOH solution if zinc was coated with Hg thinly and uniformly. Therefore, a processing of thin and uniform coating of Hg on zinc anodes was a key point to reduce Hg in alkaline batteries.Wetting of Hg on zinc in a KOH solution was evaluated using spreading coefficient (S=gamma KOH/Zn - (gamma Hg/Zn + gamma KOH/Hg)). Surface tensions of KOH solutions and interfacial tensions between Hg and KOH solutions were measured to calculate the values of S. The values of S in a KOH-Zn-Hg system were always positive and increased with an increase of KOH concentration in the system. This result indicated that a coating of Hg on zinc powder should be done in a high KOH concentration solution to achieve a thin and uniform coating of Hg.