Single Graphene Layer on Pt(111) Creates Confined Electrochemical Environment via Selective Ion Transport

Graphene is a promising candidate for an "ideal membrane material". Its ultralow (one-atomic) thickness potentially provides high permeation and at the same time high selectivity. In the presented work, it is demonstrated that these properties can be used to create a confined, two-dimensional electrochemical environment between a graphene layer and a single crystal Pt(111) surface. The well-defined "fingerprint" voltammetric characteristics of Pt(111) provide an immediate information about the penetration and intercalation of ions into the confined space. These processes are shown to be highly selective.