Formation and microstructure of nanoporous silver by dealloying rapidly solidified Zn-Ag alloys

The electrochemical dealloying of rapidly solidified (RS) Zn-Ag alloys in a 5 wt.% HCl solution and 1 M NaCl solution has been investigated using electrochemical measurements and microstructural analysis. The results show that the electrochemical properties of the RS Zn-Ag alloys are associated not only with the alloy composition, but with the phase constitution of the alloys. Nanoporous silver (NPS) ribbons can be fabricated through potentiostatically dealloying the RS Zn-Ag alloys in both solutions. Moreover, a minor difference in the applied potential has a significant influence on the dealloying process and formation of NPS. The critical potential and polarization behavior of the Zn-Ag alloys have also been discussed, as well as surface diffusion of Ag adatoms. (C) 2011 Elsevier Ltd. All rights reserved.