Selective Anchoring Groups for Molecular Electronic Junctions with ITO Electrodes

Indium tin oxide (ITO) is an attractive substrate for single-molecule electronics since it transparent while maintaining electrical conductivity. Although has been used before as a contacting electrode in studies, these studies have limited to the use of carboxylic acid terminal groups binding molecular wires ITO substrates. There thus need investigate other anchoring with potential effectively ITO. With this aim, we investigated conductance series eight tolane or “tolane-like” variety surface groups. We first gold–molecule–gold junctions identify promising targets selectivity. then assessed propensity and selectivity acid, cyanoacrylic pyridinium-squarate bind promote formation heterojunctions. found that pyridinium squarate zwitterions display excellent over gold surfaces, contact resistivity comparable acids. These experiments are complemented by chemical characterization X-ray photoelectron spectroscopy, quartz crystal microbalance, angle determination, nanolithography using atomic force miscroscope. Finally, report density-functional theory calculations involving electrodes model charge transport through ITO–molecule–gold