Iodide-induced galvanic replacement of nickel film on copper as activator for electroless nickel-phosphorus plating.

[Display omitted] • Ni was deposited on Cu by an iodide-induced unusual galvanic replacement method. • High iodide concentration was conducive to replacement deposition of Ni on Cu. • The Ni film could replace Pd and act as activator for electroless Ni-P plating. Galvanic replacement provides a convenient route to synthesize metallic films and nanostructures. However, metals commonly reduce more noble metal ions. In this work, nickel film was deposited on copper through an iodide-assisted galvanic replacement method. It was found copper had a lower electrode potential than nickel in high concentration of iodide solution, so nickel film could be obtained through the unusual galvanic replacement. The experimental results revealed increasing iodide concentration was conducive to the galvanic replacement rate between copper and nickel ions, and complete nickel film could be obtained in solution with 1200 g·L−1 sodium iodide in 10 min. The as-prepared nickel film showed good activation ability for electroless nickel-phosphorus plating, for the nickel-phosphorus coatings obtained on the nickel and traditional palladium films possessed similar morphology, structure and corrosion resistance. [ABSTRACT FROM AUTHOR]