Michel Cariou

Efficient polymer-based interpenetrated network photovoltaic cells

Organic solar cells based on an interpenetrated network of conjugated polymer as donor and fullerene derivative as acceptor materials have a great potential for improving efficiency. We fabricated a device based on a composite of poly(2-methoxy-5-(2′-ethylhexyloxy)-1, 4-phenylenevinylene and [6,6]-phenyl C60 butyric acid methyl ester. Surface treatment, insertion of interfacial layers, and improvement of the morphology of the active layer significantly increase the photovoltaic performances of the structure. We obtain an open circuit voltage of 0.87 V and short circuit current density of 8.4 mA/cm2 under 100 mW/cm2 air-mass 1.5 solar simulator illumination, yielding a 2.9% power conversion efficiency.

[4+2] Cycloaddition of C60 to 2-(thi)oxo-4,5-bis(methylene)-1,3-dithioles: en route to the bis-linking of tetrathiafulvalene to C60

Abstract The title reaction carried out from S-propargyl xanthate 3 or 2-(thi)oxo-4,5-bis(bromomethyl)-1,3-dithioles 4a and 4b with C60 is presented and some conversions of the synthesized cycloadducts 2a and 2b in several 1,3-dithiole derivatives are described.

A novel array in extended tetrathiafulvalenes (TTF): the ‘H’ shape

The highly extended, cross-conjugated and sulfur rich π-electron donor 2a was synthesized and characterized introducing the ‘H’ shape as a new approach in the tetrathiafulvalene (TTF) array.

Reduction electrochimique de propene nitriles substitues—III alkyl(aryl)oxy-3 phenyl-3 propene nitriles Z et E

The preparation and the separation of E- and Z-isomers of 3-alkyl(aryl)oxy-3-phenylpropenenitriles are described. Configurations are assigned by nmr. n nIn aqueous-organic media Z-isomers are more easily reduced than E-isomers. In anhydrous acetonitrile differences between E12 of E- and Z-isomers are smaller or null. n nPolarography, cyclic voltammetry and macro-scale reductions with identification of products permit us to propose a reduction mechanism. If Tafts constant σ* of R group is negative the Cue5fbC double bond is reduced with formation of 3-alkyl(aryl)oxy-3-phenylpropanenitriles. If σ* is positive the intermediate radical-anion loses RO− ion; cinnamonitrile is formed but immediately reduced, either to in 3-phenylpropanenitrile, or to in 3,4-diphenylhexane dinitrile. n nIt is possible to get hydrodimers while conserving OR group.

Anodic oxidation of 2,3-diarylbenzofurans : different reaction pathways for the cation radical

Abstract The electrooxidation of 2,3-diarylbenzofurans leads to a rearrangement lactone, 3,3-diaryl-2(3H)-benzofuranone, together with a ring enlargement product, 9-aroyl-9-hydroxy-(9H)-xanthene. However, in some cases coupling products may be isolated in high yield.

Differences of behaviour in electrooxidation of 3,3′-dimethoxybenzidine and its N,N,N′,N′-tetraalkylated derivatives: a further example of potential inversion

Abstract The anodic oxidation of 3,3′-dimethoxybenzidine and its derivatives were studied by cyclic voltammetry, voltammetry at a rotating platinum electrode, chronopotentiometry and constant potential coulometry. The exhaustive oxidation of 3,3′-dimethoxybenzidine led at the potential of the first oxidation peak and second oxidation peak, respectively, to a stable cation radical salt (characterized by ESR spectroscopy) and to a quinone-diimine. Whereas, 3,3′-dimethoxy- N , N , N ′, N ′-tetramethylbenzidine afforded directly a dication salt owing to potential inversion 3,3′-dimethoxy- N , N , N ′, N ′-tetraethylbenzidine gave the corresponding soluble cation radical salt.

Novel highly extended and sulfur rich tetrathiafulvalene (TTF) derivatives through an unprecedented TTF core building process

A new and unexpected tetrathiafulvalene (TTF) core building process is observed via reaction of a 1,3-dithiole phosphonate anion with a 2-oxo-1,3-dithiole functionality.

Realization and characterization of plastic photovoltaic cells

Organic solar cells based on interpenetrated network of conjugated polymer as donor and fullerene derivative as acceptor materials have a great potential for improvement of the efficiency. We fabricated a device based on a composite of poly(2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene (MEH-PPV) and [6,6]-phenyl C60 butyric acid methyl ester (PCBM). Surface treatment, insertion of interfacial layers, and improvement of the morphology of the active layer significantly increase the photovoltaic performances of the structure. We obtained an open circuit voltage of 0.87 V and short circuit current density of -8.4 mA/cm2 under 100 mW/cm2 AM 1.5 solar simulator illumination, yielding a 2.9 % power conversion efficiency. Two others fullerene derivatives were synthesized in order to get a stronger acceptor. The electrical and optical properties of devices made with MEH-PPV and these acceptors are investigated.

Electro-oxidation of diarylacetylenes and diaryldiacetylenes

Diarylacetylenes led to 1,2-diaroyl-1,2-diarylethylenes and diaryldiacetylenes led to a mixture of acetylenic α-and γ-diketones, by anodic oxidation in MeCN–LiClO4 on a graphite plate electrode.

The unusual anodic reactivity of tertiary enamines in the presence of base: the effect of the nature of the base on the product distribution

The anodic oxidation of aromatic N-methyl-N-phenylenamines leads to dimers and trimers in the presence of K2CO3, whereas in the presence of 2,6-lutidine demethylation occurs and, in one case, this is subsequent to cyclisation and results in a new 3H-indole.