Immersion zinc plating is an electroless (non-electrolytic) coating process that deposits a thin layer of zinc on a less electronegative metal, by immersion in a solution containing a zinc or zincate ions, Zn(OH)2−
4. A typical use is plating aluminum with zinc prior to electrolytic or electroless nickel plating.
Immersion zinc plating involves the displacement of zinc from zincate by the underlying metal:[1]
- 3 Zn(OH)2−
4 + 2 Al → 3 Zn + 2 Al(OH)−
4+ 4 OH−