Molecular nanodevices based on functionalized cyclodextrins

Planar nanodevices, consisted of gold electrodes in the nanometer scale fabricated by a conventional c-beam lithography and lift-off process and functionalized by suitably synthesized cyclodextrin-based self-assembled monolayers were electrically characterized. The monolayers were supramolecularly connected to gold nanoparticles, so that the electrodes were bridged. Thus, conductive paths through the cyclodextrin molecules (ideally An contact/molecule/Au bridge/molecule/Au contact) were formed. In order to study the electrical behaviour of the various samples, different arrangements were used, varying in the cyclodextrin derivative exploited, the way the CD molecules were connected the underlying gold surface and the association of the gold nanoparticles with the monolayer. Hysteresis effects that can be exploited in molecular memory devices were studied in terms of the type of the cyclodextrin complex. The transport properties as well as the topography of the cyclodextrin monolayers were also investigated by scanning tunnelling microscopy. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim