An optimised electrode pre-treatment for SAM formation on polycrystalline gold

The ability to fabricate good-quality self-assembled layers on polycrystalline gold depends sensitively on the reliable removal of contaminants inherent on ambient surfaces and the subsequent exposure of a pristine gold surface. We present here a simple method of reducing the gold oxide layer formed by the extensive oxidative treatments commonly utilised for surface cleaning. The method consists of an electrochemical reduction in the same electrolyte as used for electrochemical polishing and is demonstrated herein for both saturated alkyl and ethylene glycol thiol SAMs. The protocol is highly reproducible, and a more effective and rapid means of ensuring high chemisorbed molecular densities than chemical pre-treatment.