Electrochemical stability of self-assembled monolayers on nanoporous Au.

Desorption of thiolate self-assembled monolayers (SAMs) seriously limits the fabrication of thiol-based devices. Here we demonstrate that nanoporous Au produced by dealloying Au-Ag alloys exhibits high electrochemical stability against thiolate desorption. Nanoporous Au has many defective sites, lattice strain and residual Ag on the ligament surface. First-principles calculations indicate that these surface aspects increase the binding energy between a SAM and the surface of nanoporous Au.