Silver dendritic nanostructures protected by tetrathiafulvalene (TTF) were synthesized via reduction of silver ions with TTF in acetonitrile.

Organic-metal hybrid nanowires were synthesized by cooperative self-organization of the one-dimensional stacking of tetrathiafulvalene (TTF) via charge-transfer interaction with metallic gold originating from the redox reaction between TTF and gold ions. The nanowires can be easily obtained as purple precipitates just by mixing TTF and HAuCl4 in a CH3CN solution at room temperature. The feed molar ratio of TTF to HAuCl4 was 4.4. The average diameter and length of the observed nanowires were 90 +/- 36 nm and 15 +/- 3 microm, respectively. The formation was facilitated by the arrangement of the neutral and oxidized TTF along the one direction in a mix-valence state, which was confirmed by a broad absorption that appeared in the region of 2000 nm and the composition of the nanowires of [(TTFCl(0.78))Au(0.12)].

Silver dendritic nanostructures protected by tetrathiafulvalene (TTF) were synthesized via electron transfer from TTF to silver ions in acetonitrile, and the resulting positively charged TTF radical cations interacted with the surface of the silver dendrites. Irregularly shaped particles were visualized by scanning electron microscopy (SEM), while the silver dendritic nanostructures were found by transmission electron microscopy (TEM) due to the crystallization of the oxidized TTF after the removal of the solvent on substrates for SEM and TEM analyses. Energy-dispersive X-ray (EDX) analysis demonstrated that the particles were nanocomposites composed of the silver nanostructures and TTF. Silver and TTF were uniformly distributed in the individual particles. Both the feed molar ratio of AgNO3 to TTF and the addition of poly(vinylpyrrolidone) (PVP) as a stabilizer influenced the size and shape of the silver nanostructures. The X-ray powder diffraction, elemental, and SEM analyses of the isolated products by centrifugation indicated that the TTF-protected silver nanostructures were also formed because of the crystallization of oxidized TTF after the reaction mixture was incubated in the solution for a longer time than 5 days until the transparent solution transformed into a purple translucent dispersion. So crystallization of oxidized TTF played a major role for the formation of silver dendritic nanostructures during the evaporation of the solvent or the incubation of the silver dendrites in the solution.

Introduction. Self-assembled ultrathin multilayer films have been intensively investigated in recent years since Decher et al. introduced the method for preparing multilayer ultrathin films by the consecutive deposition of oppositely charged polyelectrolytes from dilute aqueous solution onto charged substrates. 1,2 Forces between the layers are primarily electrostatic and covalent bonds, but they can also involve hydrogen bonding and π-π interaction. Charge transfer (CT) interaction as the driven force of layer-by-layer self-assembled ultrathin films was investigated for the first time by In their work a new concept was established for the fabrication of multilayer films by consecutively alternating adsorption of two kinds of nonionic polymers, both of which have electron-donating or -accepting groups at the side chains.Recently, layer-by-layer self-assembled membranes from conjugated polymers have been prepared with the aid of electrostatic interaction, 7-10 hydrogen bonding, 11 or acid-base reaction 12 for potential applications in chemical sensors, transparent electrodes for light-emitting devices, and other molecular devices. However, conductive ultrathin films via self-assembly based on CT interaction have not been reported. Novel π-conjugated poly(dithiafulvene) (PDF) containing strong electron-donating dithiafulvene (DF) units in the main chains were recently synthesized by our group. 13 Two kinds of CT complexes of PDF with 7,7,8,14,15 or viologen derivatives, 16 were presented to reveal the strong electron-donating property of PDF. The DF units with electron-donating property in PDF backbones are involved in the CT interaction, and electron delocalization spread through the whole main chains of the oxidized π-conjugated PDF. These results motivated us to apply CT interaction between PDF and a viologen polymer as an acceptor polymer to prepare self-assembled multilayer ultrathin films as depicted in Figure 1.In this communication, we report the new layer-bylayer manipulation of PDF and the viologen polymer by CT interaction and their unique physical properties. The layer-by-layer self-assembled ultrathin film was prepared via consecutively alternating immersion of substrates into dilute dimethyl sulfoxide (DMSO) solutions of PDF and poly(hexanyl viologen) (6-VP). The charge transfer (CT) interaction formed at solid-liquid interfaces between the polymer backbones of PDF and 6-VP

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