Electrochemical deposition of nanodendritic Sn/Cu6Sn5 foam

• Metal foam with nano-sized dendrites is fabricated by co-electrochemical deposition.
• Nanodendrite is composed of Cu6Sn5 and Sn and Cu6Sn5 is embedded on the Sn dendrites.
• Alloy formation controls the deposition kinetics and results in the nano-dendrites.

Network structured porous foam with nano-sized dendrites was fabricated by co-electrochemical deposition of Cu and Sn. The foam, obtained in a Sn precursor-rich electrolyte, exhibited the open porous structure with a few hundred micrometer-sized spherical pores, while the pore wall was composed of nano-dendrites. The nano-dendrites were a mixture of Sn and Cu6Sn5, and the Cu6Sn5 alloy was embedded on the Sn dendrites. The cathodic linear sweep voltammetry of the electrochemical deposition indicated that the formation of Cu6Sn5 alloy was accompanied with Sn deposition, which reduced the foam deposition rate and resulted in the Sn/Cu6Sn5 nano-dendrites.