| Abstract
| - The facile deposition of para-substituted aryl films onto indium−tin oxide (ITO) electrodes by the electrochemicalreduction of aryl diazonium salts in acetonitrile is reported. For the deposition conditions used in this report, the arylfilm thicknesses are on the order of 1−6 nm, suggesting a multilayer structure. Regardless of the functional groupon the aryl diazonium cation, (NO2, CO2H, or fluorene) the electrodeposition behavior onto ITO electrodes is similarto that seen on other electrode materials. XPS and UV−vis data support the introduction of organic functional surfacegroups to ITO. The blocking behavior of the aryl films on ITO toward the Ru(NH3)63+/2+ redox couple is in agreementwith electron transfer through conjugated organic layers. The facile preparation of patterned aryl films with regular-spaced 700 nm voids on ITO is also described. Atomic force microscopy and scanning surface potential microscopyon patterned NO2 aryl films are used to assess the molecular structure and orientation. A 100 mV decrease in the contactpotential over NO2 aryl films relative to bare ITO suggests that the aryl films are loosely structured as deposited withthe NO2 groups oriented at a small angle away from the ITO surface.
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