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Romero-Nieto C García R Herranz MÁ Ehli C Ruppert M Hirsch A Guldi DM Martín N 《Journal of the American Chemical Society》2012,134(22):9183-9192
Electron donor-acceptor hybrids based on single wall carbon nanotubes (SWCNT) are one of the most promising functional structures that are currently developed in the emerging areas of energy conversion schemes and molecular electronics. As a suitable electron donor, π-extended tetrathiafulvalene (exTTF) stands out owing to its recognition of SWCNT through π-π stacking and electron donor-acceptor interactions. Herein, we explore the shape and electronic complementarity between different types of carbon nanotubes (CNT) and a tweezers-shaped molecule endowed with two exTTFs in water. The efficient electronic communication between semiconducting SWCNT/multiwall carbon nanotubes (MWCNT), on one hand, and the water-soluble exTTF nanotweezers 8, on the other hand, has been demonstrated in the ground and excited state by using steady-state as well as time-resolved spectroscopies, which were further complemented by microscopy. Importantly, appreciable electronic communication results in the electronic ground state having a shift of electron density, that is, from exTTFs to CNT, and in the electronic excited state having a full separation of electron density, that is oxidized exTTF and reduced CNT. Lifetimes in the range of several hundred picoseconds, which were observed for the corresponding electron transfer products upon light irradiation, tend to be appreciably longer in MWCNT/8 than in SWCNT/8. 相似文献
104.
Carbon nanotubes by design? Cyclo-para-phenylenes are monomers for the synthesis of armchair carbon nanotubes (see picture, right), and are also attractive fluorophores that display size-dependent emission properties. Geodesic polyarenes represent a realistic alternative for the rational design of carbon nanotubes through the chemical elongation of the hydrocarbon template (left). 相似文献
105.
Atienza CM Fernández G Sánchez L Martín N Dantas IS Wienk MM Janssen RA Rahman GM Guldi DM 《Chemical communications (Cambridge, England)》2006,(5):514-516
A light absorbing pi-conjugated oligomer-tetrafullerene nanoarray has been synthesized and its photophysical study reveals the presence of an intramolecular energy transfer. A phototovoltaic device fabricated from this nanoarray and poly(3-hexylthiophene) shows an external quantum efficiency of 15% at 500 nm. 相似文献
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107.
Luzzati S Scharber M Catellani M Giacalone F Segura JL Martin N Neugebauer H Sariciftci NS 《The journal of physical chemistry. B》2006,110(11):5351-5358
The photoinduced charge-transfer properties of a series of polyalkylthiophene copolymers, carrying anthraquinone substituents covalently linked to the conjugated backbone, have been studied in the solid state by photoinduced absorption (PA) and light-induced electron spin resonance (LESR) spectroscopy. The measurements indicate the formation of metastable charges arising from the photoinduced electron transfer from the polythiophene backbone to the anthraquinone moieties. At low temperatures (below 200 K), long-lived persistent charges are formed, exhibiting lifetimes that extend for several minutes; their recombination kinetics has been studied by following the formation and decay of the PA and LESR signals. The results are rationalized using a model originally proposed to describe the low-temperature recombination kinetics of long-lived photoexcited carriers in amorphous inorganic semiconductors. It is clearly evidenced that, in these polymers, the number of acceptor substituents in the chain, easily tuned by chemical tailoring, plays a key role in the photoexcitation scenario. 相似文献
108.
Altable M Filippone S Martín-Domenech A Güell M Solà M Martín N 《Organic letters》2006,8(26):5959-5962
[Structure: see text] Thermal treatment of 1,6-fullerenynes bearing an alkyl group on the terminal carbon of the alkyne moiety leads quantitatively to new allenes through a reaction mechanism involving an intramolecular ene process. This reaction outcome is in contrast to that recently found for free terminal alkynes which form cyclobutene derivatives through a [2+2] cyclization mechanism. 相似文献
109.
Reinier Lemos Dr. Kamil Makowski Dr. Luis Almagro Dr. Blanca Tolón Dr. Hortensia Rodríguez Dr. M. Ángeles Herranz Dr. Dolores Molero Prof. Dr. Nazario Martín Prof. Dr. Margarita Suárez 《European journal of organic chemistry》2023,26(7):e202201301
Cyclopropanation reactions between C60 and different malonates decorated with monosaccharides and steroids using the Bingel-Hirsch methodology have allowed the obtention of a new family of hybrid compounds in good yields. A complete set of instrumental techniques has allowed us to fully characterize the hybrid derivatives and to determine the chemical structure of monocycloadducts. Besides, the proposed structures were investigated by cyclic voltammetry, which evidenced the exclusive reductive pattern of fullerene Bingel-type monoadducts. Theoretical calculations at the DFT-D3(BJ)/PBE 6-311G(d,p) level of the synthesized conjugates predict the most stable conformation and determine the factors that control the hybrid molecules′ geometry. Some parameters such as polarity, lipophilicity, polar surface area, hydrophilicity index, and solvent-accessible surface area were also estimated, predicting its potential permeability and capability as cell membrane penetrators. Additionally, a molecular docking simulation has been carried out using the main protease of SARS-CoV-2 (Mpro) as the receptor, thus paving the way to study the potential application of these hybrids in biomedicine. 相似文献
110.
The first main-chain copolymer containing TCAQ and enantiomerically pure binaphthyl moieties connected at 2,6 positions of the TCAQ ring was successfully synthesized by means of a polycondensation reaction. Cyclic voltammetry investigations show that TCAQ preserves its acceptor ability in the polymer system and preliminary photophysical investigations show fluorescence quenching in mixtures containing the acceptor polymer and fluorescent conjugated polymers. 相似文献