A simple facet-based method for single crystal electrochemical study

In this paper, we demonstrate a simple facet-based method for single crystal electrochemical study. Based on the design of a simple and proper electrochemical cell using a cone-shaped pipette tip, one of the natural (1 1 1) facets of a Au single crystal bead has been directly used for electrochemical measurements. Since the processes of orientating, cutting and mechanical polishing are avoided, misorientation and mechanical damage to single crystal surface can be eliminated and reliable data are expected. The advantages of the method have been proved by the nice cyclic voltammogram of Ag underpotential deposition (UPD), a system that has shown large discrepancy in cyclic voltammograms reported by different laboratories due to the dissimilarity of the surface state. The sharp and reversible UPD peaks from the facet-based measurements resemble the best of the reported data in the literature. The method can be extended to (1 1 1) surfaces of some other metals.