Direct route to well-defined, chemically diverse electrode arrays

The selective placement of molecules of interest at specific locations on surfaces is a keystone for the bridge between interfacial science and technology. One approach to this problem is the use of electrochemistry to direct interfacial reactions that immobilize species from solution onto surfaces. In this study, sets of individually functionalized gold electrodes were formed by the selective formation of monolayers from four different alkyl thiosulfates. Analysis of the arrays using spatially resolved X-ray photoelectron spectroscopy (XPS) revealed each type of functionality exclusively on the electrode to which it was directed. The wetting behavior of these surfaces was also consistent with homogeneous monolayers placed selectively on each electrode. The flexibility of this method provides the ability to produce a wide variety of chemical patterns at interfaces of interest for a range of technological applications.