Electrochemical metallization of molecular adlayers

Abstract

Electrochemical metallization of molecular adlayers allows the sandwiching of a group of molecules between a metallic substrate and a metal nanoisland or nanocluster through a wet process not requiring expensive vacuum equipment and with precise control through the electrode potential. These metal–molecule–metal sandwiches could provide a simple means to integrate molecules in electronic circuits or to explore effects arising because of quantum confinement of electrons due to the reduced dimensions of the islands or clusters deposited on the adlayer. Although initial attempts resulted in penetration through the adlayer and direct deposition on the metal substrate, the development 14 years ago of a two-step technique involving preadsorption of the target cation on the self-assembled monolayer before its reduction in an electrolyte not containing that cation opened a whole new range of possibilities. In this brief review, we discuss the development and recent advances in the implementation of this technique and briefly discuss the outlook for future work.