title: Selective anodic desorption for assembly of different thiol monolayers on the individual electrodes of an array.
abstract: The close proximity of two individually addressable electrodes in an interdigitated array provides a unique platform for electrochemical study of multicatalytic processes. Here, we report a "plug-and-play" approach to control the underlying self-assembled monolayer and the electroactive species on each individually addressable electrode of an interdigitated array. The method presented here uses selective anodic desorption of a monolayer from one of the individually addressable electrodes and rapid formation of a different self-assembled monolayer on the freshly cleaned electrode. We illustrate this strategy by introducing variations in the length of the linker to the electroactive species in the self-assembled monolayer, which determines the rate of electron transfer. In order to separate the assembly of the monolayer from the choice of the electroactive species, we use CuI-catalyzed triazole formation ("click" chemistry) to covalently attach an acetylene-terminated electroactive species to an azide-terminated thiol monolayer selectively on each electrode. The resulting variations in the electron-transfer rate to surface-attached ferrocene and in the rate of catalytic oxidation of ascorbate by the ferrocenium/ferrocene couple demonstrate an application of this approach.
authors.affiliation: Department of Chemistry, Stanford University, Stanford, California 94305, USA. jpc@stanford.edu
authors.forename: James P
authors.initials: JP
authors.lastname: Collman
authors.forename: Ali
authors.initials: A
authors.lastname: Hosseini
authors.forename: Todd A
authors.initials: TA
authors.lastname: Eberspacher
authors.forename: Christopher E D
authors.initials: CE
authors.lastname: Chidsey
mesh_terms: D000327:Adsorption; D004566:Electrodes; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D013438:Sulfhydryl Compounds