Formation of oriented molecular nanowires on mica surface

Abstract

Molecular ''nanowire'' structures composed of the charge transfer complex of a bis-tetrathiafulvalene substituted macrocycle and tetrafluorotetracyanoquinodimethane were constructed on mica substrates by employing the Langmuir-Blodgett technique. The nanowires transferred from a dilute aqueous potassium chloride subphase had typical dimensions of 2.5 nm ؋ 50 nm ؋ 1 m. The nanowires are oriented to specific directions, corresponding to the directions of the potassium-ion array on the mica surface having sixfold symmetry. Such correlation between the nanowires and the substrate surface was also observed when a dilute aqueous rubidium chloride subphase was used. On the other hand, the correlation completely disappeared when the subphase contained divalent cations, indicating that the molecular nanowires orient by recognizing the monocation array on the mica surface. The nanowires formed by the vertical dipping method coexist with the monolayers. Only nanowire structures are, however, observed when we apply the horizontal lifting method. Based on the crystal structure of a related complex, a possible structure of the nanowires is presented. The conductivity of the nanowires was estimated to be of the order of 10 ؊3 S⅐cm ؊1 . The nanowires formed specific (regular) structures such as T-shape junctions, suggesting their use in construction of future molecular nanoscale devices.

Self-assembly and micellization of amphiphilic rod–coil block oligomer at the mica–water interface

“…The similarly oriented arrangement of self-assemblies on mica has also been found in other systems, which is thought to result from the template inducement of a metal-ion array on the crystalline lattice surface of mica having sixfold symmetry [24,[30][31][32]. In our recent work, we also reported that the Langmuir-Blodgett films of a rod-coil block oligomer with a shorter PEO coil than EO 16 OPV could present the oriented rod-like domains on mica [21].…”

Nanohybridized Synthesis of Metal Nanoparticles and Their Organization

“…Organic conducting 1D nanostructures have been studied with the expectation for potential application owing to their low density and flexibility for molecular design compared with the inorganic nanostructures [170][171][172][173]. Despite a variety of synthetic methods to the organic 1D nanostructures, creation of template-free and facile approaches are still required for future practical application [174,175]. Naka and Chujo [176] introduced the synthesis of organic-metal hybrid nanowires via electron-transfer reaction between tetrathiafulvalene (TTF) and a gold ion.…”

Interfacial Organization of Y‐Shaped Rod–Coil Molecules Packed into Cylindrical Nanoarchitectures

“…Oriented structures of p-conjugated polymers on mica substrates have also been reported. [27][28][29][30] Akutagawa et al indicated that nanowires are oriented along the direction of the metal-ion array on a mica surface with sixfold symmetry during transformation of the film. [27] Li et al reported a rod-coil molecule containing a PEO block with seven repeating units similar to 18-crown-6, which is capable of recognizing a K + cation array on the mica surface with sixfold symmetry.…”

“…[27][28][29][30] Akutagawa et al indicated that nanowires are oriented along the direction of the metal-ion array on a mica surface with sixfold symmetry during transformation of the film. [27] Li et al reported a rod-coil molecule containing a PEO block with seven repeating units similar to 18-crown-6, which is capable of recognizing a K + cation array on the mica surface with sixfold symmetry. [28] In our case, the number of ethylene oxide repeating units of the Y21 molecule is three times that of the rod-coil molecule reported by Li et al, and the PEO block with 21 repeating units could also interact with K + cations according to the sixfold symmetry axes of the mica substrate.…”