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A bis-tryptophan tweezer was installed on a polyoxometalate (POM) surface via a bis-amide covalent bond, yielding the enantiopure hybrid POM with C2 symmetry, as a result of the regioselective functionalization of decatungosilicate [γ-SiW10O36]8– at the lacunary site. The combined polyanionic and receptor properties are instrumental for a POM-driven solubilization and enrichment of single walled carbon nanotubes (SWCNTs) with diameter

Nanodispersions of pristine single-wall carbon nanohorns (i.e., p-SWCNHs) and oxidized-SWCNHs (i.e.; o-SWCNHs) were used to modify screen printed electrode (SPE). p-SWCNHs and o-SWCNHs were fully characterized by using several analytical techniques, as: HR-TEM (High Resolution-Transmission Electron Microscopy), FE-SEM/EDX (Field Emission-Scanning Electron Microscopy/Energy Dispersive X-ray Analysis), Raman spectroscopy, thermogravimetric analysis, differential thermal analysis (DTA), and the Brunauer-Emmett-Teller (BET) method. The chemically modified SPEs were also characterized with Cyclic Voltammetry (CV), using several different electro-active targets. In all cases, p-SWCNHs showed better performances than those obtained for o-SWCNHs as well as with respect to conventional Glassy Carbon (GC) electrodes, in terms of peak currents, significant shift at lower redox-potential ranges and enhanced heterogeneous apparent kinetic constants.

Perylene-3,4,9,10-tetracarboxylic acid bisimides have been widely studied as industrial pigments. Lately, these dyes have drawn considerable attention because of applications as photocatalysts and organic semi-conductors. Here, we report a novel method for fast and efficient synthesis of many different perylenebisimides, based on microwave-assisted reactions.

PCBM is a fullerene derivative (phenyl-C61-butyric acid methyl ester) considered to be one of the best n-type organic semiconductors and plays a relevant role in organic photovoltaic solar cells. Much effort has been devoted to the optimization of the synthesis of PCBM derivatives. In this paper, PC61BM and PC71BM fullerene mono-adducts but also PCBM-like derivatives are successfully prepared by a one-step cyclopropanation reaction under microwave irradiation. The products are collected in good yields in short time, during which isomerization of the open [5,6] to the closed [6,6] form takes place in situ. In addition, with the use of two cycles of irradiation, a series of mixtures of bis-adduct PCBM-like derivatives were also obtained in good yields.

Covalent functionalization of single- and multiwalled carbon nanotubes was performed by using a cyclopropanation reaction under classical heating conditions. The method involves the in situ formation of diazo intermediates, which are generated from tosylhydrazone precursors. The covalent functionalization of the pristine materials was evaluated with the use of characterization techniques such as thermogravimetric analysis and Raman spectroscopy. All compounds were also characterized by UV/Vis/near-IR and transmission electron microscopy. Similar to the example of fullerene-type derivatives, this procedure can produce new materials that may be appropriate for devices such as solar cells.

We present the Raman bands of nano-graphene flakes (NG flakes) produced by oxidation of single-walled carbon nanotubes. These bands overlap with the defect-induced Raman modes of carbon nanotubes. This can lead to an overestimation of the defect density in the nanotubes. Here we analyze the line shape and the dispersion of this superimposing Raman band of NG flakes. Furthermore, we investigate the predicted Raman band of NG flakes next to the high-energy Raman modes ( and ) of the nanotubes. Raman spectra of the defect-induced Raman mode of nanotubes after oxidation with the contribution of NG flakes.

The synthesis and characterization of sidewall-functionalized SWNT derivatives (nPrNH)(n)-SWNTs containing n-propylamine addends is reported. The nucleophilic addition of in situ generated lithium n-propylamide to the sidewall of SWNTs and the subsequent reoxidation of charged intermediates of the type (nPrNH)(n)-SWNTn- leads to carbon nanotube derivatives with covalently attached amino groups. Based on the reaction sequence, a homogeneous dispersion of the carbon nanotube material is achieved as a result of the electrostatic repulsion of negatively charged intermediates. The solubility of the resulting propylamine-functionalized (nPrNH)(n)-SWNT material in organic solvents is drastically increased. The functionalized tubes were characterized in detail by Raman spectroscopy, thermogravimetric analysis (TGA/MS), X-ray photoelectron spectroscopy (XPS) and UV/Vis/NIR spectroscopy. ((c) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008). European Journal of Organic Chemistry