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。溶解速率从大到小依次为（0001）单晶面、多晶面、（1100）单晶面。有人建议，溶解速率取决于平面的原子密度。在锌表面均匀地镀上一层薄薄的汞后，极少量的汞对防止锌在KOH溶液中的自溶解起了很大的作用。采用铺展系数（S= γ KOH/Zn -（γ Hg/Zn + γ KOH/Hg））评价了汞在锌电极上的润湿性。测定了KOH溶液的表面张力和Hg与KOH溶液的界面张力，计算了S值。在KOH-Zn-Hg体系中，S值始终为正值，且随体系中KOH浓度的增加而增大。这一结果表明，汞在锌粉上的包覆应在高浓度的KOH溶液中进行，以获得薄且均匀的汞包覆。

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.