Deposition of polyheterocycles on spontaneously adsorbed monolayer-modified electrodes

The kinetics of electrooxidative polymerization, and the structure and properties of polyheteroarenes, are strongly dependent on the surface characteristics of the electrode. Deposition of spontaneously adsorbed monolayers (SAMs) affords a fast, efficient method of modifying electrode behavior towards electroactive monomers in contacting solutions. The modification also has profound effects on the properties of the electrooxidatively deposited polyheteroarenes. Monolayers of ω-(3-pyrrolyl)alkanethiols, 4-(3-pyrrolyl)butyl ω-mercaptoalkanoates, and ω-mercaptoalkyl (3-pyrrolyl)acetates modify the noble metal-solution and metal-polymer interface. The monolayer provides covalently bound nucleation sites on the surface, thereby enhancing the initial rate of deposition of heteroarenes from solution. The resulting polyheteroarene films are smooth, densely packed, highly conductive and particularly robust compared to those deposited on unmodified metal electrodes.