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A dialkylamino-subtituted oligophenylenevinylene (OPV) derivative bearing a fullerene subunit (F–D) has been prepared. The electrochemical properties of F–Dhave been investigated by cyclic voltammetry. Whereas the first reduction is centered on the C60unit, the oxidation is centered on the dialkylamino subunit of the OPV rod. In F–D, both the OPV and the fullerene-centered fluorescence bands are quenched and this suggests the presence of photoinduced electron transfer from the amino-substituted OPV to the carbon sphere. By means of bimolecular quenching experiments, transient absorption spectral fingerprints of the radical cationic species have been detected in the VIS (670 nm) and NIR (1300–1500 nm) regions, along with the much weaker fullerene anion band at λmax= 1030 nm. Intramolecular photoinduced electron transfer occurs in the investigated dyad and a relatively long-lived charge-separated state has been detected, with a lifetime of 135 and 85 ns in toluene and benzonitrile, respectively. The longer lifetime in the less polar solvent suggests a Marcus inverted region behavior for the charge recombination process. [ABSTRACT FROM AUTHOR]

Since the discovery of C60 fullerene, carbon-based nanostructures have become one of the hottest research topics in science. During the past decade research efforts have mainly been devoted to the investigation of C60 and carbon nanotubes, although the ability of carbon to exist in different allotropic forms has provided a variety of nanoscale size shapes with fascinating properties. In this article we highlight some of the most representative examples that document the scientific progress accomplished in this field which, surprisingly, started with a serendipitous discovery. [ABSTRACT FROM AUTHOR]

Fullerene derivatives bearing a pyridine sub-unit have been prepared. Their ability to form self-assembled supramolecular structures with mono- and polytopic Zn(ii)–porphyrin receptors has been first evidenced by UV-vis studies. These supramolecular complexes are multi-component photoactive devices, in which the emission of the porphyrinic receptor is dramatically quenched by the fullerene units. This new property, resulting from the association of the different molecular sub-units, also allowed us to investigate in detail the self-assembly process using fluorescence titrations. The binding studies revealed positive cooperative effects for the assembly of the C60–pyridine derivatives with polytopic receptors as a result of intramolecular C60–C60 interactions between the different guests assembled onto the multi-Zn(ii)–porphyrin hosts. [ABSTRACT FROM AUTHOR]

A 2-pyrazolino[60]fullerene-based triad, possessing two TTF units connected with flexible long linkages, has been prepared. Fluorescence quenching was observed in polar and non-polar solvents, suggesting the existence of a through-space photoinduced charge separation process with rates faster than 3.8 × 109 s−1 and with high efficiency (>0.85). The charge separated states were confirmed by transient absorption spectra in the visible and near-IR regions. The longest lifetime of the charge separated state was found to be 230 ns in CH2Cl2 solvent. [ABSTRACT FROM AUTHOR]

Mixtures of an appropriate carboxylic acid and n-butylstannoic acid constitute modular gelation systems, in which the formation of a well-defined ‘tin-drum’ nanocluster subsequently underpins the hierarchical assembly of nanostructured fibres, which form self-supporting gel-phase networks in organic solvents. [ABSTRACT FROM AUTHOR]