Fabrication and Wettability of Nanoporous Silver Film on Copper from Choline Chloride-Based Deep Eutectic Solvents

http://pubs.acs.org/doi/abs/10.1021/jp105182y

Nanoporous Ag films on copper alloy substrates were fabricated by the galvanic replacement reaction from
the choline chloride-based deep eutectic solvents (DES) containing AgCl. It was found that the morphologies
of the films were largely dependent on AgCl concentrations and plating temperatures. Interestingly, selfassembled nanoporous network of Ag films with ligament and channel width in the range of 20-80 nm was
formed on the copper alloy substrate from 0.01 M AgCl DES solution either at room temperature or at 50 °C.
The as-deposited porous Ag films exhibited hydrophilic properties. On the contrary, after surface modification
by a monolayer of n-dodecanethiol, the contact angle of porous Ag film increased largely with plating times,
and a superhydrophobic surface was finally obtained with a contact angle of 160 ( 1°. Wenzel and
Cassie-Baxter models were used to qualitatively illustrate the importance of the surface roughness of the Ag
films to the wetting property.