Formation of water-insoluble nanographene adlayers using water-soluble micelle capsules

Abstract

Polycyclic aromatic hydrocarbons (PAHs) such as dicoronylene and C₉₆H₃₀, the so-called "nanographenes" are excellent building blocks for the creation of two-dimensional (2D) and/or epitaxial thin films. However, large PAHs tend to exhibit no solubilities in not only water but also organic solvents. To overcome this issue, water-soluble micellar capsules consisting of V-shaped amphiphilic molecules was employed. Using electrochemical scanning tunneling microscopy, we demonstrate that our molecular containers based on the water-soluble molecular capsules allow the facile preparation of 2D PAH adlayers in addition to structurally controlling nanostructure formation on Au electrode surfaces. PAHs were released from the capsules in especially acidic solutions, resulting in the formation of a 2D adlayer of PAHs at the electrochemical interface.