88949-33-1Relevant articles and documents
Post-deposition activation of latent hydrogen-bonding: A new paradigm for enhancing the performances of bulk heterojunction solar cells
Bruni, Francesco,Sassi, Mauro,Campione, Marcello,Giovanella, Umberto,Ruffo, Riccardo,Luzzati, Silvia,Meinardi, Francesco,Beverina, Luca,Brovelli, Sergio
, p. 7410 - 7419 (2014)
Small conjugated molecules (SM) are gaining momentum as an alternative to semiconducting polymers for the production of solution-processed bulk heterojunction (BHJ) solar cells. The major issue with SM-BHJs is the low carrier mobility due to the scarce control on the phase-segregation process and consequent lack of preferential percolative pathways for electrons and holes to the extraction electrodes. Here, a new paradigm for fine tuning the phase-segregation in SM-BHJs, based on the post-deposition exploitation of latent hydrogen bonding in binary mixtures of PCBM with suitably functionalized electron donor molecules, is demonstrated. The strategy consist in the chemical protection of the H-bond forming sites of the donor species with a thermo-labile functionality whose controlled thermal cleavage leads to the formation of stable, crystalline, phase-separated molecular aggregates. This approach allows the fine tuning of the nanoscale film connectivity and thereby to simultaneously optimize the generation of geminate carriers at the donor-acceptor interfaces and the extraction of free charges via ordered phase-separated domains. As a result, the PV efficiency undergoes an over twenty-fold increase with respect to control devices. This strategy, demonstrated here with mixtures of diketopyrrolopyrrole derivatives with PCBM can be extended to other molecular systems for achieving highly efficient SM-BHJ solar cells.
IMPROVED, RED COLOUR FILTER COMPOSITION
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Page/Page column 52, (2009/12/27)
A composition, for producing dispersions, thermoplastic masses and/or colour filters, comprising (a) a colourant of formula (1) wherein 20-100 mol% R1 are Br and 80-100 mol% R3 are H, especially of formula (Ib) and /or (Ic); (b) from 0 to 150 % by weight, based on (a), of C. I. Pigment Red 144, 188, 190, 224, 242 or 2,4,6-trimethylphenylperylene diimide; (c) from 3 to 25 % by weight, based on (a), of a di- or tri-azacyclopentylmethyl-substituted colourant (formulae given); (d) from 0 to 10 % by weight, preferably from 0.01 to 8 % by weight, based on the sum of (a) and (b), of an additionally sulfonated colourant of the same kernels as in (c); and (e) from 0 to 30 % by weight, preferably from 3 to 25 % by weight, especially from 5 to 20 % by weight, based on (a), of a diketopyrrolopyrrole colourant substituted by at least one chain containing a plurality of nitrogen atoms (cf. formula (V)). The compound of formula (Ig), wherein R20 and R22 are, each independently of the other, H, Cl, Br, CN, CF3, R22, OR22, SR22, SOR22, SO2R22, NR23COR22, COOR23, CONR22R23, CONH2, CON(R22)2 or CON(R24), preferably Cl, Br, CN or R22, wherein R22, in each case independently of any other R22, is C1-C5alkyl, C2-C5alkylene, phenyl or 2-naphthyl, preferably methyl or phenyl, R23, in each case independently of any other R23, is H, d-C5alkyl or C2-C5alkylene, preferably H Or CH3, and R24, in each case independently of any other R24, is C4-C8alkylene which is uninterrupted or interrupted one or more times by NR23, NOR23, O, S, SO or by SO2, R24 in N(R24) forming with N a preferably 5- or 6-membered heterocyclic ring, with the proviso that R20 and R21 are not simultaneously Br and H, respectively, and also solid solutions thereof are likewise claimed. Also claimed is the compound of formula (Vb), wherein R27 is Br, Cl, F or methyl, R28 is H, C1-alkyl, or C6-C12alkyl wherein a carbon atom has been replaced by a nitrogen atom, and R29 is C6-C18alkyl wherein 1 or 2 carbon atoms has/have been replaced by nitrogen atom(s).
Direct preparation of pyrrolo[3,4-C]pyrroles
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Page column 17,18, (2008/06/13)
A process is disclosed for the direct preparation of pigmentary 1,4-diketopyrrolo-[3,4-c]pyrroles of the formula (I) wherein each of R1and R2independently of the other is an isocyclic or heterocyclic aromatic radical, which process comprises heating an appropriate molar ratio of a disuccinate with a nitrile of the formula (II) R1—CN??(II) or of the formula (III) R2—CN??(III) or with mixtures of said nitrites, in an organic solvent and in the presence of a strong base and an effective amount of a selected particle growth inhibitor of formula (IV)-(X), and then obtaining the compound of formula (I) from the reaction product by protolysis. The process yields pigmentary 1,4-diketopyrrolo-[3,4-c]pyrroles directly, i.e., without the need for additional particle-size reducing aftertreatments. Also disclosed is a composition comprising a pigmentary 1,4-diketopyrrolo-[3,4-c]pyrrole and the particle growth inhibitor. These pigment compositions are useful for pigmenting high molecular weight organic materials.