Highly soluble air-stable conjugated decamers and polymers (compounds 1–6) with alternating “sulfur-overrich” bis­(3,4′-S-alkyl)-2,2′-bithiophenes as the donor units and 2,1,3-benzothiadiazoles as the acceptor units were designed and expediently synthesized with the aid of microwave and ultrasound enabling technologies. Solid-state cyclovoltammetry showed that 1–6 had oxidation and reduction potentials in the range 0.6–0.9 V and −1/–1.2 V (vs SCE), respectively, with energy gaps below 2 eV. The electronic properties of spin-coated films of pure 1–6 were investigated with nanoscale resolution by Kelvin probe force microscopy (KPFM). KPFM measurements showed that charge generation and separation were obtained for all films under illumination. Consequently, 1–6 were tested on single-material organic solar cells (SMOCs). In agreement with KPFM results, photovoltaic behavior was observed for all compounds with power conversion efficiencies in line with the best results obtained so far for the few donor–acceptor molecules already shown to perform in single-component solar cells. To our knowledge, this is the first time in which thiophene–benzothiadiazole co-oligomers and copolymers are shown to be photoactive materials in SMOCs.

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In this article, we present the synthesis and characterization of a new thiophenic copolymer bearing the C 60 fullerene directly linked to the end of a hexamethylenic side chain. This copolymer was prepared with good yield using a simple and straightforward post-polymerization functionalization procedure applied on a soluble regioregular polymeric precursor obtained by regiospecific organometallic coupling. Copolymer structural and photophysical properties were investigated by gel permeation chromatography, thermal analysis (DSC and TGA), NMR, IR, UV-Vis, and atomic force spectroscopy. The double-cable copolymer possesses good solubility in common organic solvents, high filmability, thermal stability, and low segmental aggregation tendency. It was tested as a photoactive layer in a polymeric solar cell showing a power conversion efficiency under 100 mW cm 22 AM 1.5 illumination higher than 4%, more than that of the reference cell made with the conventionally used P3HT/PCBM blend.

Distinct batches of orange (1a-e) and green crystals (2a-e) were isolated from the reactions of MoCl5 with tetrahydropyran (thp), respectively at room temperature (in CH2Cl2) and at ca. 80 °C (in ClCH2CH2Cl). Crystals 2a-e are isomorphous to 1a-e and the IR spectra are almost superimposable. 1a-e were identified by X-ray studies as cis-MoCl4(thp)2, in agreement with previous findings. Careful refinement of the X-ray data of 2a-e by modeling one position as disordered between chlorine (minor component) and oxygen (major component) led to the conclusion that 2a-e consisted of a mixture of cis-MoCl4(thp)2 and mer-MoOCl3(thp)2, the latter being largely prevalent.

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