ChemInform Abstract: Electronic Communication in Tetrathiafulvalene (TTF)/C60 Systems: Toward Molecular Solar Energy Conversion Materials?

Departamento de Química Orgánica, Facultad de Ciencias Químicas, Universidad Complutense, E-28040 Madrid, Spain.
Accounts of Chemical Research (Impact Factor: 22.32). 11/2007; 40(10):1015-24. DOI: 10.1021/ar700026t
Source: PubMed


The covalent connection of the electron acceptor C 60 to p-quinonoid pi-extended tetrathiafulvalenes (exTTFs) has allowed for the preparation of new photo- and electroactive conjugates able to act as artificial photosynthetic systems and active molecular materials in organic photovoltaics. The gain of aromaticity undergone by the pi-extended TTF unit in the oxidation process results in highly stabilized radical ion pairs, namely, C 60 (*-)/exTTF (*+). Lifetimes for such charge-separated states, ranging from a few nanoseconds to hundreds of microseconds, have been achieved by rationally modifying the nature of the chemical spacers. These long-lived radical pairs are called to play an important role for the conversion of sunlight into chemical or electrical power.

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    • "TTF derivatives now play a significant role as redox sites in different areas of supramolecular chemistry. Some applications call for their use as cations sensors [7–9] as a π-electron donor for non-linear optical systems [10–12], heterocycles [13–15], integrated into polymeric [16–18] and dendritic systems [19] and used as a component for molecular electronic devices [20–22]. "
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    ABSTRACT: The synthesis of new unsymmetrically benzene-fused bis (tetrathiafulvalene) has been carried out by a cross-coupling reaction of the respective 4,5-dialkyl-1,3-dithiole-2-selenone 6-9 with 2-(4-(p-nitrophenyl)-1,3-dithiole-2-ylidene)-1,3,5,7-tetrathia-s-indacene-6-one 5 prepared by olefination of 4-(p-nitrophenyl)-1,3-dithiole-2-selenone 3 and 1,3,5,7-tetrathia-s-indacene-2,6-dione 4. The conversion of the nitro moiety 10a-d to amino 11a-d then dibenzylamine 12a-d groups respectively used reduction and alkylation methods. The electron donor ability of these new compounds has been measured by cyclic voltammetry (CV) technique. Charge transfer complexes with tetracyanoquino-dimethane (TCNQ) were prepared by chemical redox reactions. The complexes have been proven to give conducting materials.
    International Journal of Molecular Sciences 03/2014; 15(3):4550-4564. DOI:10.3390/ijms15034550 · 2.86 Impact Factor
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    • "In this process, photons are absorbed and re-emitted, which results in the occurrence of energy relaxation from high energy wavelength to low energy wavelength. Therefore, these materials have wide applications including organic field-effect transistors [1], organic light-emitting diodes [2], organic photovoltaics [3] [4] [5] and biochemical sensors [6]. On the other hand, these ␲-conjugated compounds can also be used as wavelengthshifting materials to improve performance of cadmium telluride (CdTe) solar cells. "
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    Journal of Photochemistry and Photobiology A Chemistry 01/2013; 251:1–9. DOI:10.1016/j.jphotochem.2012.10.002 · 2.50 Impact Factor
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    • "The synthesis of compounds 1a–d from 4,7- dibromobenzo[c][1] [2] [5] "
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