Effect of Additive on the Formation of Cusn Alloy Nano-Trees Formed with DC Electroplating
There is a significant effect of additive (PEG) for the formation of nano tree structure as shown in Fig.1. If there is no addition of PEG, deposited Cu-Sn alloy has a round rock shape only (Fig.1-a). However, when adequate amount of PEG is added to the plating bath, a very interesting nano-tree structure grows almost perpendicularly to the substrate (Fig.1-b). The top view of the nano-tree clearly shows branches are formed with 4-fold symmetry.
Nano-tree has a huge ratio of surface area to its volume, and is regarded as a typical three-dimensional nano-porous structure. The nano-tree may have a high potential to be used for electrode of Li-ion batteries, as well as chemical sensors when it is oxidized.